1. Chromosomal features in the spermatogonial metaphase and anaphase. The investigations have been undertaken based on the chromosomal slides prepared according to the current air-drying squash method. Chromosomes were examined in spermatogonial metaphase and early anaphase in the following 7 butterfly-species: Papilio maackii (2n,60); Papilio bianor (2n,60); Polygonia c-aureum (2n,62); Argyreus hyperbius (2n,62); Curetis acuta (2n,58); Favonius latifasciatus (2n,48); and Narathura japonica (2n,48). They are reproduced in Figs.1-12. In general, the mitotic chromosomes have been furnished as objects for the determination of chromosomal form in organisms in numerous surveys of karyological studies. As a whole, the mitotic chromosomes provide favorite materials for chromosome analysis from the following reason that the chromosomes of M-I cells are usually presented by a structure of bivalents characterized by their chiasmata. On the basis of the chromosomal aspects derived from the mitotic metaphases observed in the above-mentioned species, the author was not able to obtain any evidence indicating that V- or J-shaped metacentric chromosomes are included in the diploid complements of the butterfly. As seen in micrographs of early anaphases shown in Figs.7-12, every chromosome divided each into two elements which took a parallel arrangement. With the advance of the stage these sister chromatids took the start-action to each opposite pole. The chromosomal features and behavior as seen at the early anaphase were nearly identical to those observed in some Hemiptera such as Euschistus and Solubea by HUGHES-SCHRADER & SCHRADER (1961). The latter authors have described in their paper that in anaphasic disjunction the separating chromatids remain parallel to each other as they move "broadside on" to the pole. 2. Chromosomal features and behavior in the M-I metaphase and anaphase. The following investigations were undertaken based on the chromosome preparations according to the ordinary acetoorcein squash method, and also phase contrast was applied for more detailed analysis. Chromosome features depicted at M-I metaphase and anaphase in the following two species: Graphium sarpedon (n,20) (butterfly) and Eumeta variegata (n,31) (moth), are presented in Figs.13-25. The prereductional phenomenon of the bivalents in Lepidoptera had been established on the basis of the behavior of fragment chromosomes studied through the mitotic and meiotic divisions of G. sarpedon (MAEKI and HAYASHI, 1979). It was shown that the first division was reductional, whereas the second division was equational. Here, noteworthy was the finding that the bivalent chromosomes of Lepidoptera were constructed by "a ring of four" (LA COUR, 1952) at the M-I metaphase (Figs.13-17,22-23). The general features of chromosomes of G.sarpedon and E. variegata at the M-I anaphase are remarkable by the appearance displaying "pseudo-V-shape" in outline (see Figs.18-21, 24-25). In the course of the first anaphase the two sister chromatids moved to the same pole, and then the two chromatids (or a half-bivalent) having the pseudo-V-shape spread gradually along a straight line from each other. It appeared that the spindle fibers attached themselves to the whole poleward surface of the two rods of each sister chromatid. This behavior followed closely the synchronized activity of their spindle fibers. Most reasonable estimation from the above observations seems to be in favor of the view that the formation of the "pseudo-V-shaped" chromosome results from the association of the two rod-shaped elements equipped with the diffuse kinetochore structure. 3. Chromosome morphology and behavior in the M-II cells. In the equatorial plate of M-II metaphase two sister chromatids of a rod-type appeared taking a linear arrangement in each, as seen in Fig.26. If the chromosomes were telocentric carrying a

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