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1961

Journal of the Lepidopterists' Society

175

A STUDY OF INTERSPECIFIC HYBRIDS IN BLACK SWALLOWTAILS IN JAPAN

by Shigeru Albert Ae

There are four species of black swallowtails in Japan, which resemble each other somewhat closely. They are Papilio protenor demetrius Cramer, P. macilentus Janson, P. helenus nicconicolens Butler, and P. memnon thunbergii von Siebold, and all are Rutaceae feeders. Any combination of interspecific crossing of these swallowtails may produce hybrid butterflies and they may give some data on genetics of characters which separate species, and on evolutionary processes in these species, as in the study of the Papilio machaon group (Clarke & Sheppard, 1953, 1955a, 1955b, 1956a, 1956b; Remington, 1958, 1960; Ae, 1960). There are two other species of black swallowtails in Japan, P. bianor dehaanii C. & R. Felder and P. maackii tutanus Fenton, which have brilliant green and blue scales all over the upper side of the fore and hind wings. They resemble each other, and both are Rutaceae feeders. Hybridization studies of these species may also give data of the kind which was noted above.

The writer started to work on hybridization of the above black swallowtails at Nanzan University, Nagoya, Japan, in 1959 and obtained hybrid adults (Figs. 2a & 5a) between P. helenus (Fig. la) and P. protenor (Fig. 3a) and between P. bianor (Fig. 4a) and P. maackii (Fig. 6). The work will be continued to obtain more data. However, the obtained data clarified the main characters of the Fi hybrids of the above two kinds and gave some indications of interspecific relations. Therefore, the writer presents these data here.

P. protenor is very common and P. helenus is somewhat uncommon in Japan. A mixed flight of several individuals of each species on a flowering plant is not an unusual sight in certain localities. P. helenus is distributed in Japan, Taiwan, Philippines, South and West China, Thailand, Burma, India, Malaya, Sumatra, Java, and Borneo, etc., and divided into many subspecies. P. protenor is distributed in Japan, Korea, Taiwan, Middle and West China, Burma, and North India, etc., and divided into several subspecies. P. bianor is common all over Japan and P. maackii is also found all over Japan except most of the lowland of the southern half, but is not so common as P. bianor. P. bianor is distributed in Saghalien, Korea, Manchuria, China, Taiwan, and North Burma besides Japan. P. maackii is distributed in Korea, Manchuria, Amur, and Taiwan besides Japan.

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Materials

In May, two females of P. protenor, R-7-8 and R-7-10, were successfully hand-paired with a wild P. helenus male which was collected at Jokoji, near Nagoya. The above two females emerged from overwintering pupae of Brood R-7, which was obtained from eggs laid by a female collected in Nagoya. The larvae of this brood were reared on Inuzansho (Fagara schinifolia Engl.). In July, six females of P. protenor, R-15-1, R-15-2, R-16-5, R-16-8, R-16-14 and R-16-16, were successfully hand-paired with six males of P. helenus, of which five were collected at Hirayama and Nagao region near Shizuoka, Shizuoka Prefecture, and one at Jokoji. These six females emerged from pupae of Broods R-15 and R-16, which were obtained from eggs laid by females collected respectively in Nagoya, and at Jokoji. In September, a female of P. helenus was successfully hand-paired with a wild male of P. protenor, which was collected in Nagoya. This female emerged from pupae of Brood N-9, which was obtained from eggs laid by a female collected at Hirayama and Nagao region. The individual designation of a female was also used as the designation of its brood. The designation of a brood was used as the prefix of individuals in the brood.

On May 30, the writer collected a male of P. maackii, spring form, at Tsubame Hot Spring, Mt. Myoko, Niigata Pref. The butterfly was brought back to Nanzan University in good condition and hand-paired with 3 females of Brood D-9 of P. bianor: to D-9-13 on May 31, to D-9-14 on June 1, and to D-9-15 on June 2. The mother of Brood D-9 was collected at Jokoji in August, 1958. The larvae, which hatched from eggs laid by this female, were reared on Inuzansho and they overwintered in the pupal stage. The pupae were kept in the ice box until May 7 and brought out to the laboratory.

Duration of Copulation

The technique of hand-pairing (Clarke & Sheppard, 1956b) was used for all matings. Minutes in copulo in Table 1 shows the approximate duration of copulation in protenor X helenus and maackii X bianor matings, from which eggs were obtained later. It is not certain what is a minimum effective duration of copulation. In the writer's many inter-and intra-specific matings in hand-pairings as well as in usual cage matings, a sufficient duration is usually 60 minutes, when copulation is normal. However, some copulations of less than 60 minutes were also fertile. Remington's data in Papilio (1960) show a sufficient duration

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can be 30 minutes. There may be a great difference according to the kinds of crossing. In the writer's experiments reported here, when a couple separated within 15 minutes, another attempt at hand-pairing was made and was usually successful immediately or some time later. The five P. protenor females which copulated with P. helenus males for more than 30 minutes did not lay any eggs and these data are omitted from the Table 1. The P. bianor female, D-9-14, above mentioned, also laid no egg.

Fertility of Matings

Table 1 shows the fertility of matings. An egg has yellowish white color, when it is laid. If it starts to develop, a brown mottling or ring appears in P. protenor and P. helenus and in the hybird between them. This color change was used for an indicator of fertilization. However, no color change appears in P. bianor and P. maackii nor the hybrid between them in an early stage of development. The writer has as yet found no way to detect fertilization from superficial observation in these species. When a larva is well formed within the egg shell, the egg of these species and their hybrid turns black.

All or a part of the copulations in Table 1 which resulted in no fertile eggs may have been abnormal, although they are indistinguishable from other copulations which resulted in some fertile eggs. P. protenor females R-7-8 and R-7-10 were hand-paired with the same wild P. helenus male, N-l, firstly to R-7-8 and secondly to R-7-10. This male was previously hand-paired with three P. xuthus Linne females, and two of these females laid a few fertile eggs in spite of the wide crossing. The mate of P. helenus female, N-9-4, was a wild P. protenor male and was previously also hand-paired with a P. bianor female. This male may have copulated previously in the field. Therefore, the low fertility of the above three matings could have been the result of the shortage of spermatozoa. However, the data are by no means sufficient to conclude this. Although no data are available on intraspecific hand-pairings of the parental species at present, fertility of wild females shows some indication as a control (Table 1). Wild females of P. protenor had high egg fertility and hatchability in this experiment. However, a female of P. helenus, N-20, had very low fertility. This may also probably be the shortage of spermatozoa, since this female was collected toward the end of the flying season. Egg fertility, 98.2%, in Brood R-16-8 may indicate that egg fertility in hybrid P. protenor X helenus is as high as in intraspecific

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B.     Controls (wild P. protenor)

R-15 112                   112 112                   112

R-16 138                   136 136                   135

R-28 38                     38 36                     36

C.     Controls (wild P. helenus)

N-9 55                     50 50                     50

N-10 6                       5 4                       3

N-20 76                       9 9 4 ----

D. $ P. bianor X $ P- maackii

D-9-13 38                      - 7                       4 60-120

D-9-15 2-00         60-120

E. Controls (wild P. bianor)

D-14 69                      - 57 57 ----

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matings in the best situation. The low egg fertility in other cases may be a mechanical failure and/or an effect of different compatibility against a partner of hybrid crossing by individual hereditary differences of parental species. Mechanical failure could involve hereditary differences in copulating organs besides a mere shortage of spermatozoa. Therefore, at present one could say that a crossing between P. helenus and P. protenor in Japan has a high egg fertility in the best condition environmentally and probably hereditarily. However, using the technique of hand-pairing means a complete bypass of courting behavior, which is very important in natural matings. Therefore, wild hybrids may not be produced at all in spite of wide sympatry between the two species.

Data are too small to discuss fertility of matings between P. bianor and P. maackii in general. Hatchability of one crossing obtained is as low as 10.5%.

Developmental and Survival Rates

Table 2 shows the developmental rates of the hybrids and their controls. The rates of the fastest developing individuals on different food-plants were recorded. Because of irregular death rates due to virus diseases during development, reliable data on average and slowest developmental rates could not be obtained.

The rearing was carried out at the window side of the laboratory room. The morning sun shone in the room until a little before noon. Since the rearing was carried out at the room temperature, temperature differences during development must be considered. Comparison of four broods of P. protenor reared on Inuzansho gives an indication concerning the temperature differences; lengths of their larval stages were 36 days in May-June, 30 days in July - August, and 22 and 28 days in August - early September. The differences of developmental rates due to foodplant differences are prominent in P. helenus and the hybrid P. helenus X P. protenor. Only Inuzansho was used for the rearing of P. protenor, because of the shortage of the other food plants. The developmental rates of the hybrids between P. helenus and P. protenor seem to have no prominent difference in comparison with the parental species, although constant temperature rearing conditions are desirable for more accurate data.

P. bianor and the hybrid between P. bianor and P. maackii seem to have approximately the same developmental rate. A little delay in P. bianor may be seasonal, because the rearing of P. bianor was started 9 days earlier than the hybrid.

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Table 3 shows the survival rates in larval and pupal stages in the parental species and the hybrids when reared on the different foodplants. P. helenus and P. protenor are both Rutaceae feeders. However, some specificity in foodplants is known in nature. According to Shirozu (1959), in Japan P. helenus larvae feed on Kihada (Phellodendron amurense Rupr.), Karasuzansho (Fagara ailanthoides Engl.), Karatachi (Poncirus trifoliata Rafin.), Sansho (Xanthoxylum piperitum DC), Yuzu (Citrus junos Tanaka), Unshumikan (Citrus unshiu Marcov.), etc. P. protenor larvae feed on Yuzu, Unshumikan, Karatachi, Sansho, Inuzansho,

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Journal of the Lepidopterists' Society

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Table 3. LARVAL SURVIVAL RATES IN PAPILIO HYBRIDS AND CONTROLS.

* Larvae of this brood reared on mixed food plants were omitted from this table.

Miyamashikimi (Skimmia japonica Thunb.), Karasuzansho, Goju (Evodia rutsecarpa Hook. fil. & Thorns.), Kinkan (Fortunella japonica Swingl.), etc. Data indicate that while P. protenor larvae have rather high survival rates on Inuzansho, P. helenus larvae have rather low survival rates on it. P. helenus larvae have higher survival rates on Natsumikan (Citrus natsudaidai Hayata) and Karatachi than on Inuzansho. The hybrids showed the same tendency as P. helenus. The hybrids also showed good development on Kihada.

Keeping these results in mind, and reconsidering the data on Table 2, the slower developmental rates of P. helenus and the hybrids between

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P. protenor and P. helenus on Inuzansho in comparison with the other food plants may also indicate the unsuitability of foodplant.

P. bianor larvae feed on Kokusagi (Orixa japonica Thunb.), Kara-suzansho, Kihada, Sansho, Inuzansho, Karatachi, etc. and P. maackii larvae feed on Kihada, Hirohanokihada, Karasuzansho, Hamasendan, etc. P. maackii does not seem to be able to feed on more kinds of foodplants than P. bianor. It is known that in Japan P. maackii is distributed in warm lowlands only where its food plants are found and is absent from other warm lowlands in which only the foodplants used by P. bianor are found (Shirozu, 1959).

The larval hybrids between P. bianor and P. maackii were reared on Inuzansho and fed on it readily. However, since Inuzansho is not a usual foodplant of P. maackii, this plant may not be the most suitable foodplant for the hybrid.

Expression of Interspecific Differences in Hybrids

1. P. protenor X P. helenus.

Larval differences between Papilio protenor and P. helenus are very slight. A detailed study of large series will be necessary to show the differences. The writer's superficial observations on each of more than 20 larvae of the parental species and the hybrids during the rearings showed a somewhat prominent difference only on the 5th instar larvae (Figs, lb, lc, 2b, 2c, 3b, 3c); the stripe on the 6th abdominal segment is almost or entirely discontinuous at three points on P. helenus and is continuous on P. protenor. This stripe on the hybrid is usually discontinuous, and therefore it resembles P. helenus.

Pupae of P. helenus and P. protenor are distinguishable only on the mid-ventral bend, on which the angle is sharper on P. helenus than on P. protenor (Figs. Id & 3d). Pupae of the hybrids (Fig. 2d) seem to be indistinguishable from pupae of P. helenus.

Most of the hybrids emerged during the summer. They are much smaller than summer forms of wild P. helenus and P. protenor. However, butterflies reared in a laboratory are usually smaller than wild butterflies. Therefore, a comparison should be made with laboratory reared specimens. Pupal lengths of the reared specimens were measured for this purpose. Table 4 shows the results. The hybrids are not necessarily smaller than the parental species according to these data, although more data are necessary for a final conclusion.

In all, 15 hybrid butterflies were obtained, 2 from Brood R-7-8, 10 from Brood R-16-8, and 3 from Brood N-9-4 (Fig. 2a). All of them were males and some of them failed to extend their wings fully.

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Table 4. PUPAL LENGTHS OF HYBRIDS AND PARENTAL SPECIES.

* Only part of the pupae obtained were measured. ** Over-wintering pupae were not measured.

The most prominent difference between adult P. helenus and adult P. protenor is the presence of white patches on the hind wings of P. helenus. These patches cover a part of cells Sc-Ri, R2, and Mi, and extend quite often to a part of cells M2, M3, and M4 (Fig. la). The "Com-stock-Needham" system is applied here to name the cells. These patches do not exist in P. protenor (Fig. 3a), but in P. protenor the male has a white band in cell Sc-Ri of the hind wing. The white patches of P. helenus are also seen on the under side of the wing, but the dorsal white band of P. protenor is not seen on the under side. These white patches and band appear in the hybrid, but their development is not as clear as in the parental species, especially on the boundaries of the patches and the band. In the hybrid the patch and the band on Sc-Ri overlap but only partially; therefore the presence of both characters is

PLATE 1                                                                                  PAPILIO HYBRIDS

^Fu ^

ib

2b

Id

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obvious. The white patches on cells M2 and M3 are very scant or disappear in the hybrids (Fig. 2a). In one hybrid specimen, all white patches are reduced to a trace on the under side of the wings, although they are clear on upper side.

The general shape of both the fore and hind wings is easily distinguishable between parental species. This shape in the hybrids resembles F. helenus.

All hybrids have more or less red scales on the basal parts of the white patches of the hind wings. These red scales are not seen either on F. helenus nor on P. protenor.

On the under side of the fore wing of both species, white scales are partially superimposed on the blackish scales which cover the whole wing. On the cells of R5, Mi, M2, M3, and Cut of F. protenor, white scales are superimposed on all areas except the wing margin and the central part of each cell (Fig. 3a). On the same cells of F. helenus, a scant white band of the same width is formed through the central part of each cell (Fig. la); therefore, no white scales are seen on the basal part of each cell, a clear difference from F. protenor. In the hybrids (Fig. 2a), the expression of these white scales is quite close to that of F. protenor; but the basal part of cell Cu3 has no white scales, as in F. helenus.

On the abdomen of F. helenus, one lateral and three ventral white lines are usually distinct. The same lines are not clear or are absent on the abdomen of F. protenor. In the hybrids, the expression of these lines is somewhat intermediate between the parental species.

2. F. bianor X F. maackii.

Larval differences between F. bianor (Fig. 4b) and P. maackii are very slight. Although there are many minor differences, the writer failed to compare them precisely, since he could not rear larva3 of F. maackii with P. bianor and the hybrid. The most prominent difference may be a pair of small processes at the 9th abdominal segment. These processes are more prominent in F. maackii than F. bianor, especially at the late larval stages. The hybrid seems to be intermediate or maackii-like (Fig. 5b).

EXPLANATION OF PLATE 1

PAPILIO HELENUS: la) adult $ (underside at right); lb) mature larva, dorsal; lc) same, lateral; Id) pupa, lateral.

PAPILIO F1 HYBRID ( 9 PROTENOR X $ HELENUS): 2a) adult $ (underside at right); 2b) mature larva, dorsal; 2c) same, lateral; 2d) pupa, lateral.

PAPILIO PROTENOR: 3a) adult $ (underside at right); 3b) mature larva, dorsal; 3c) same, lateral; 3d) pupa, lateral.

PLATE 2

PAPILIO HYBRIDS

PAPILIO BIANOR: 4a) adult $, summer form (underside at right); 4b) mature larva, lateral; 4c) pupa, dorsal.

PAPILIO Ft HYBRID (9 BIANOR X $ MAACKII): 5a) adult $, summer form (underside at right); 5b) mature larva, lateral; 5c) pupa, dorsal.

PAPILIO MAACKII: 6) adult $, spring form (underside at right).

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The shapes of pupae of P. bianor (Fig. 4c) and P. maackii are indistinguishable. However, coloration of pupae is variable within and between species. Pupae of P. bianor are usually green or brown, and the overwintering and non-overwintering forms are distinguishable. Besides these colorations, yellowish-brown and greenish-brown colors appeared in the writer's rearings. Yellowish-brown pupae have a prominent median dorsal brown line, and this coloration resembles both of the hybrid pupae (Fig. 5c) obtained. However, published figures of pupae of P. maackii seem to resemble more closely the hybrid pupae.

The sizes of the two hybrids are smaller than wild summer specimens of P. maackii and most wild summer specimens of P. bianor. However, they are as large as P. bianor of Brood D-14 which were reared in the laboratory at approximately the same time as the hybrids.

Adults of P. bianor and P. maackii resemble each other very closely (Figs. 4a & 6). There is no single character which separates both species clearly. However, one can identify typical specimens easily. The characteristics which separate the species are as follows. 1) P. maackii generally has well developed bands of light color along the inside of the outermargin of the upper side of fore and hind wing; however, these bands become very scant or completely disappear from hind wing in some individuals. P. bianor lacks these bands completely. 2) P. maackii has a yellow band along the inside of the outer margin on the under side of the hind wing, and P. bianor never has this band. However, P. maackii lacking this band are sometimes found in the warmer regions of Japan. 3) A white band on the under side of the fore wing is wide at the apical area and becomes narrow toward the outer angle in P. bianor. This band has a uniform width in P. maackii. Since these characteristics of P. maackii are clearer in the spring form than in the summer form, a spring form is used for Fig. 6; the hybrids emerged in summer.

The expression of these characters in the two hybrids (Fig. 5a) obtained is as follows. 1) The bands of light color on the upper side are prominent in one individual and scant in the other. In both the boundaries of the bands are not as clear as in P. maackii. 2) The yellow band on the under side of the hind wing is absent in both. 3) The white band on the under side of the fore wing is somewhat wider toward the apical area and is intermediate between the condition in the typical parental species.

The Problem of Over-wintering

If Papilio larvae are reared toward the end of the summer in a laboratory, usually part of the resulting pupae emerge after a normal pupal period and others pass the winter and emerge the following spring.

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In the writer's 1959 rearing, pupae of Brood R-33 of P. protenor, which resulted from eggs laid at the middle of August, produced 6 adults from Sept. 13 to October 1; the remaining 14 pupae overwintered. Pupae of Brood N-9 of P. helenus, which resulted from eggs laid at the end of July, produced 5 adults from August 29 to Sept. 10; the 2 remaining pupae overwintered. However, all three pupae of Brood N-9-4 (hybrid P. protenor X P. helenus), which resulted from eggs laid at the beginning of September, emerged from October 21 to November 5. Although the data are still too small, the hybrid pupae seem to lack the ability to "diapause", which is very important for survival of a species in winter.

Back-cross Attempts

Three hybrid males of Brood R-18-6 (P. protenor X P. helenus), which were reared on Natsumikan, were successfully hand-paired with females of the parental species. The first one copulated with a P. protenor female for about 30 minutes. The second also copulated with a P. protenor female, but this couple failed to separate from each other and were forced to separate after about 15 hours. These two females failed to lay any eggs. The third hybrid male copulated with a P. helenus female for about 1 hour. The formation of a spermatophore was observed from the outside just after separation. However, this female was very weak and died the next day without laying eggs.

One of the hybrid males between P. bianor and P. maackii was hand-paired with 2 females of P. bianor, Brood D-14. Both copulations lasted about one hour and the formation of spermatophores was confirmed just after the separation at the second mating. From the first and the second matings, 17 and 39 eggs respectively, were obtained. However, no egg turned black, and of course none hatched.

Discussion

The average egg fertility (35.5%) and the average egg hatchability (20.6%) of the hybrids between P. protenor and P. helenus may indicate that the relationship of the two species is not close. However, the high egg fertility (98.2%) and the somewhat high egg hatchability (82.3%) from one cross may indicate that at least some individuals of the two species still retain a somewhat close relationship. Since all 15 hybrid butterflies were males, Haldane's Rule applies in this hybrid combination. The female is presumed to be heterogametic in butterflies. The red scales on the basal parts of the white patches of the hind wing in the hybrid

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between P. protenor and P. helenus may be an example of an appearance of a concealed hereditary character through a change in gene background by a hybridization. If a hybrid lacks the ability to diapause, as the data suggest, this phenomenon would be an important factor in preventing the establishment of a hybrid population in nature.

Although the characters of the hybrids between P. bianor and P. maackii were clarified extensively by the two hybrid males obtained, the data are still too small to discuss the compatibility relation between the parental species.

Since P. protenor and P. helenus are sympatric in Japan, as are P. bianor and P. maackii, the existence of natural hybrids must be considered, although a hand-pairing by-passes normal courtship behavior completely, as previously stated. The writer sent photographs of the two kinds of hybrids to Dr. T. Shirozu, Kyushu University, and he wrote to the writer that he has never seen a specimen which resembles the writer's hybrid between P. protenor and P. helenus, but he has occasionally seen specimens which resemble the hybrid between P. bianor and P. maackii. Therefore, the difficulty in distinguishing wild P. bianor and P. maackii may be due partially to natural hybridization and resulting introgression.

Summary

1.     Four fertile matings between P. protenor female and P. helenus male, one fertile mating by a reciprocal cross, and one fertile mating between P. bianor female and P. maackii male were obtained, using a technique of hand-pairing.

2.     The durations of copulation in the hybrid matings were recorded, and those of the fertile matings lasted about one to two hours.

3.     The average egg fertility in the five crosses between P. protenor and P. helenus was 36.5% and the average egg hatchability was 29.6%. The highest hybrid egg fertility was 98.2% and the highest egg hatch-ability was 82.3%.

4.     The egg hatchability of the cross between P. bianor and P. maackii was 10.5%.

5.     The developmental rates of the hybrids do not seem to differ extensively from the developmental rates of the parental species in the above two kinds of hybrid. Differences of developmental rate and larval survival due to foodplant differences were prominent in P. helenus and in the hybrids between P. protenor and P. helenus.

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6.    Characteristics of the hybrids between P. protenor and P. helenus and between P. bianor and P. maackii were compared to those of the parental species.

7.    Haldane's Rule fits both hybrid combinations. All 15 hybrid P. helenus X P. protenor were males. The 2 hybrid P. bianor X P. maackii were also males.

8.    The pupae of the hybrid between P. protenor and P. helenus seem to lack the ability of diapause.

9.    Three back-cross hand-pairings using the Fx hybrids between P. protenor and P. helenus and two using a Fi hybrid between P. bianor and P. maackii were obtained, but no eggs hatched and no fertilization could be found.

10.    Existence of natural hybrids between P. protenor and P. helenus and especially between P. bianor and P. maackii must be considered.

Acknowledgement

The writer wishes to express his sincere gratitude to Dr. Charles L. Remington, Department of Zoology, Yale University, for reading this paper in manuscript and to Rev. Francis Bures, S. V. D. for help in writing this paper. He is also grateful to Dr. T. Iwase and Mr. M. Takahashi for help in collecting P. helenus, to Dr. T. Shirozu for examination of the pictures of the writer's hybrids. A fund was supplied from the Ministry of Education in Japan in 1959.

Literature Cited

Ae, S. A., 1960. A study of hybrids between Papilio xuthus and the P. polyxenes-

machaon group. Journ. lepid. soc. 14: 5-18, 2pls. Clarke, C. A., & P. M. Sheppard, 1953. Further observations on hybrid swallowtails.

Entomologist's record 65, supplement: 12 pp., 7 pis. ..............., 1955a. A preliminary report on the genetics of the machaon group of

swallowtail butterflies. Evolution 9: 182-201, 5 figs. ................, 1955b. The breeding in captivity of the hybrid swallowtail Papilio

machaon gorganus Fruhstorfer $ X Papilio hospiton Gene $ . Entomologist 38:

266-270, 4 pis. ..............., 1956a. A further report on the genetics of the machaon group of swallowtail butterflies. Evolution 10: 66-73, 1 fig.

..............., 1956b. Hand-pairing of butterflies. Lepid. news 10: 47-53, 3 figs.

Remington, C. L., 1958. Genetics of populations of Lepidoptera. Proc. X. int.

congress ent. 2: 787-805, 13 figs. ..............., 1960. Wide experimental crosses between Papilio xuthus and other

species. Journ. lepid. soc. 13: 151-164, 3 pis. Shirozu, T., 1959. [The section of butterflies.] Iconographia insectorum Japoni-

corum colore naturali edita: Vol.1 (Lepidoptera).

Biological Laboratory, Nanzan University, Nagoya, JAPAN