1. In the present paper the bodies in the cytoplasm which stain vitally with aqueous solution of Janus green (cf. Sorokin 1938) are designated as chondriosomes in the cells of Polypodiaceous plants.
2. The plastids and chondriosomes are distinct from each other and exist side by side in all the stages of the life cycle. The latter stains vitally with aqueous solution of Janus green, while the former does not.
3. The plastids and chondriosomes increase in number by their own division.
4. In general, the plastids are larger than the chondriosomes, but in some cases the former become smaller resembling the chondriosomes. Even the latter cases these two types of bodies can be distinguished from each other when aqueous solution of Janus green is used.
5. In the spore several plastids (leucoplasts) and many chondriosomes which are small granulous, rodlet-like or rosary-like are observed.
6. Before germination of the spore the leucoplasts change into chloroplasts. In the prothallium cell there are many large chloroplasts and small chondriosomes.
7. In the spermatogenous cell there are observed from several to ten small leucoplasts and many chondriosomes.
8. In the spermatid from several to ten small leucoplasts and many chondriosomes are contained. As the spermatozoid approaches to its completion the leucoplasts become larger, accumulating starch grains within them.
9. The plastids and chondriosomes of the spermatozoid are cast away during the active swimming of the spermatozoid.
10. In the young egg cell large spherical leucoplasts (several to ten) and many small granulous, rodlet-like or rosary-like chondriosomes are seen. In the completed egg cell all the chondriosomes are granulous.
11. The plastids and chondriosomes of the new plant derive from these of the egg cell only.
12. In the cells of sporophyte many large chloroplasts and small granulous, rodlet-like or rosary-like chondriosomes are contained. In the case of subterranean stems, roots and rhizoids the leucoplasts and chondriosomes are seen in the cell.
13. During the course of sporogenesis the spore mother cell contains small leucoplasts and chondriosomes which are gathered on the separation plane of anaphase in meiosis and distributed into the spore cells.
14. In the spore cells several leucoplasts and many chondriosomes are contained. As the spore cell approaches its completion the leucoplasts gradually increase in their size.

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Burnt (Bu) is a dominant mutant which appeared in the offspring of the pupae treated with X-rays. In F₂ generation of burnt, much more than 25% of the total eggs are inviable and the segregating ratio of burnt to normal is about 2:1. It is assumed that the homozygous individuals for Bu are perfectly killed in the embryonal stage. These lethal embryos live so long as the setae are completely formed. They can, however, never enter reversion and all die away. Imperfect formation of amnion on the dorsal direction, and no-closing of the “Rücken-naht” and of the mid-gut seem to check the further development. The function of the gene Bu, when homozygous, appears at the stage between elongate and reversional.

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1. By treating the silkworm eggs within 2.5 hours after laying with colchicine solution of various concentrations from 0.05 to 0.4%, many polyploid individuals were obtained.
2. Polyploid worms were detected both genetically and cytologically.
3. It is assumed that diploid and polyploid egg cells are mixed with one another in the ovaries of the polyploid individuals induced by colchicine treatment.

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The spermatogonial metaphase of Hybris subjacens invariably shows 22 chromosomes (Figs. 1-4). All the chromosomes seem to be telomitic in the fibre attachment and slightly variable in their length. So far as the number and shape of the chromosomes are concerned, this species shows no marked difference when it is compared with the following four other species of the Ascalaphidae so far studied: Ascalaphus libelluloides, A. longicornis, Ogcogaster segmentator and Glyptbasis dentifera. An even number of chromosomes in the male diploid group suggests the existence of the sex chromosome constitution of the usual X-Y type.
There are found, at metaphase of the primary spermatocyte, 11 bivalent chromosomes (Figs. 6-7). Of these 11 elements, 10 are autosome bivalents and the other is the X-Y complex which is conspicuously recognized in the lateral view of the spindle, showing a remarkably precocious segregation into its components, X and Y (Figs. 8-9). Since the X is completely separated from the Y in the first division, two kinds of secondary spermatocytes are formed. The one group, the X-class, consists of 10 autosome dyads plus an X element; the other is the Y-class which contains a Y element with a similar complex of autosome dyads (Figs. 10-11).
The occurrence of elongated or V-shaped centrioles was ascertained in the spermatocytes of the present species. In the primary spermatocyte metaphase the two V-shaped centrioles, with their widely diverging rod-like arms, assume their respective positions at opposite poles (Fig. 8). Their form and behaviour in the spermatogonial and secondary spermatocyte divisions were briefly observed (Figs. 5, 9 and 12).

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[in Japanese]

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A Lycoris sp. grown in China shows very similar morphology to L. radiata (2n=33). However, they are clearly distinguished by difference in the fertility, i.e. the Chinese Lycoris gives the normal production of seeds but L. radiata is completely sterile.
On the other hand, the karyological feature of the Chinese Lycoris, e.g. number and morphology of chromosomes, is similar to that of L. sanguinea(2n=22). That is, it has 22 diploid chromosomes, showing nearly terminal attachment of spindle-fibres. At first metaphase in PMC, bivalents usually show the characteristic shape as illustrated in Fig. 6.
The sterility of L. radiata is clearly due to the autotriploidy which is probably induced by triplication of the genom of the Chinese Lycoris or allied species.

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As a well-known character in Pharbitis Nil, we find a crumpled leaf which is uneven on the surface, frequently rolling up on the brim. In common cases this character behaves as a recessive to normal. These are, crumpled-1 (c₁) in the variegated linkage group, crumpled-2 (c₂) in the delicate linkage group found by Imai, and crumpled-3 (c₃) in the cordate linkage group found by the author.
A new gene, crumpled-4 (c₄) for this character, is studied in the present paper. Crossing experiments have shown the results that the gene links respectively to white flower (c) with the recombination frequency 31.4%, and to speckled (s_p1) with 31.2%. Both frequencies should be nearly equal because of having a close linkage between c and s_p1.
According to the author's previous studies, white flower (c) links to a gene r of other white flower with 24.6%, speckled (s_p1) links to a gene (s_p2) of other speckled flower with about 25%, and a close linkage occurs between s_p2 and r. Therefore, it should be expected that a linkage occurs between c₄ and r. The linkage occurrence of one crossing gave the result to be agreeable to this expectation, there by the recombination frequency between these genes being 33.6%.
Considering these linkage studies mentioned above, such a conclusion that these four genes arranged with the order c₄-s_p1-c-r on a chromosome may be introduced.
Several other linkages described in the present paper, which maple (m) links to yellow 2 (y₂) with 36.6%, to r with 48.0%, y₂ links to r with 44.4%, and m links to c₄ with 38.4%; together with other linkages which dusky (d_y) links to yellow 1 (y₁) with high intensity, to c₄ with 37.4%, and c₄ links to y₁ with 37.6%, comfirm the former author's proposition that the speckled linkage group is put into the yellow one.
A new gene “crumpled-4” (c₄) of a crumpled leaf is considered to be a member of the yellow linkage group, and its locus is located between yellow 2 and speckled 1.

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[in Japanese]

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