Click here for the original journal page (in Acrobat pdf format).

The text below is grayed out because it is not intended to be read. It is a necessarily imperfect OCR of the original and is only used by a search engine.

36

Vol.7, no.2

CHROMOSOME NUMBERS OF SOME JAPANESE RHOPALOCERA

by Kodo Maeki and Sajiro Makino

The order Lepidoptera has long furnished favorite material for cytological study, and extensive studies of the chromosomes have been carried out, mainly from the cyto-taxonomic standpoint. With reference to the list of the chromosome numbers in animals, published by Makino (1951), it is evident that the list of the known chromosomes in the Heterocera, or moths, including about 170 species, is larger than for the Rhopalocera, of which about 150 species are known. So far as the authors are aware, the comparative studies of the chromosomes have been published by Beliajeff (1930), Federley (1938), Lorko-vic (1941), and some others, mainly with European butterflies. Our knowledge of the chromosomes of Japanese butterflies, however, is very meager. In view of this the present authors have undertaken the chromosome study of Japanese species of butterflies since 1951, to contribute something in this unexplored field, and made clear the chromosome numbers of 52 species of butterflies which were mostly obtained in the vicinity of Sapporo, Hokkaido. This report seems to furnish the first comparative study which deals with butterfly chromosomes in Japan.

All the butterflies used as material for the present study were collected during 1951 and 1952. They belong to seven families. They include 52 species of the Rhopalocera, namely: 1 species of Libytheidae, 7 species of Lycaenidae, 21 species of Nymphalidae, 5 species of Papilionidae, 7 species of Pieridae, 8 species of Satyridae, and 3 species of Hesperiidae. In most cases, the testes obtained from mature adults were used in this study. For the fixatives, Allen's P. F. A.-3 solution, Allen-Bouin's mixture, Allen's B-3 solution, and Benda's fluid were employed. The sections were made according to the paraffin method and stained with Heidenhain's iron-haematoxylin with a counter-stain of light green.

In all species studied here, the spermatogonial chromosomes were not observed. The haploid chromosomes in both primary and secondary spermatocytes came under study. It is notable that the chromosome number of Pieris melete shows a variation ranging from 27 to 31. The basic number was determined as 27. The cause of the numerical variation lies in the presence of supernumerary chromosomes. The supernumeraries vary from 1 to 4, each represented by a minute element. The species coming under study and the chromosome numbers established are listed in the table. The species having numbers around 30 (n) are most numerous, being 73% in frequency. The chromosome number of the species studied ranges from 14 to 36; between these extremes the following numbers; 24, 25, 26, 27, 28, 29, 30, 31 are represented. The species having 31 chromosomes (n) are most frequent, being 35%. Those with 30 chromosomes rank second. The numerical condition found in the present study is quite similar to that in moths. Among the species concerned here, there is no evidence for the presence of polyploidy.

The authors wish to acknowledge their gratitude to Dr. C. L. Remington, of Yale University, who kindly recommended that we publish this short note in The Lepidopterists' News, while the senior author (S. M.) visited his laboratory.

1953

The Lepidopterists' News

CHROMOSOME NUMBERS OF JAPANESE BUTTERFLIES STUDIED BY THE AUTHORS

Species Hesperiidae

Daimio tethys Men. Halpe varia Murray Parnara guttata Brem. & Gray

Papilionidae

Papilio xuthus Linne

Papilio machaon hippocrates Feld.

Papilio maackii Men.

Papilto protenor demetrius Cram.

Papilio bianor Cram.

PlERIDAE

Aporia crataegi Linne Anthocaris scolymus Butler Colias hyale Linne Eurema hecabe Linne Pieris rapae Linne Pieris napi Linne Pieris melete Men.

Satyridae

Coenonympha oedippus Fab. Lethe diana Butler Lethe sicelis Hew. Mycalesis francisca per dice as Hew. Mycalesis got a ma Moore Neope goschkevitschii Men. Satyrus dryas Scop. Yythima argus Butler

LlBYTHEIDAE

Libythea celtis Fuessl.

LYCAENIDAE

Celastrina argiolus Linne Neozephyrus taxila Bremer Curetis acuta par acuta Nice. Lycaena phlaeas Linne Zizeeria maha argia Men. Everes argiades Pallas Arhopala japonic a Murray

Nymphalidae Argynnis charlotta Argynnis laodice Pallas ' Argynnis ruslana Motsch. Argynnis paphia Linne Argynnis anadyomene Felder Aglais urticae Linne Apatura ilia Schiff. Araschnia burejana Brem. Araschnia levana Linne Brenthis ino Rott. Hestina japonic a Feld. & Feld.

n (haploid number)

& Feld.

in ID

31 (I, ID

# (I) denotes the first spermatocyte and (II) the second spermatocyte.

38

MAEKI & Makino: Chromosome Numbers                 Vol.7, no.2

Kaniska canace Linne Limenitis Camilla Schiff. Limenitis glorifica Fruhst. Neptis aceris Lep. Nymphalis io Linne Nymphalis xanthomelas Esper Polygonia c-album Linne Polygonia c-aureum Linne Sasakia charonda Hew. Vanessa indica Herbst

References

Beliajeff, N. I., 1930. Die Chromosomenkomplexe und ihre Beziehung zur Phylogenie

bei den Lepidopteren. I^eitschr. indukt. Abst. Vererb. 54: 369-399. Federley, H., 1938. Chromosomcnzahlen finnlandisher Lepidopteren. I. Rhopalocera.

Hereditas 24: 397-464. Lorkovic, Z., 1941. Die Chromosomenzahlen in der Spermatogenese der Tagfalter. Chro-

mosoma 2: 155-191. Makino, S., 1951. An atlas of the chromosome numbers in animals, 2nd ed. Iowa State ^College Press, Ames. 290 pp. Zoological Institute, Faculty of Science, Hokkaido University, Sapporo, JAPAN

THE EXCELSIOR COMPLEX

by Nicholas Shoumatoff

In view of the variety of interesting hypotheses offered recently to explain the phenomenon of acrophilia in butterflies — their habit of sometimes lingering on hilltops — it may be helpful to recapitulate, and at the same time offer a simpler classification of alternatives, as follows:

General Type                             Reference

Biological

Specific Cause Search for foodplant Emergence on hilltop Search for females Wind Tropism Gregariousnness Liking hilltops Social ambition Male battleground

Involuntary Element of Play

Competition

Merritt, Lepid. News 6:101 Arnhold, Lepid. News 6:99

Merritt, Lepid. News 6:101

Rawson, Lepid. News 5:70

In analyzing this problem, I believe it is important to distinguish between the influences of macro- and microtopology. The former involves the well known phenomena of isolation of Lepidoptera on mountain tops due to vertical temperature gradient or geological history. I assume it is only the question of small, local hilltops that is at issue here.