Broodiness of F₁ hybrids, produced by the crosses, White Leghorn _??__??_×Barred Plymouth Rock _??__??_ was examined. The Plymouth Rock hens used were those of non-broody strain which was obtained by prolactin-experiment.
All of the 29 hybrid hens obtained from the crosses in which non-broody White Leghorn Cocks were used, were non-broody.
The above is perhaps the result of the perfectness of broodiness-elimination in the maternal line.
Average days from birth to the laying of first egg in these hybrids, and the average number of eggs laid by them during the 1st year, are as follows:

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1. A large bamboo-grove round the Shinhama Duck-netting Pond (Imperial House Hold) at the mouth of River Edo, Gyotoku, Chiba Prefecture, offers roost for many thousands of Grey Starlings, Sturnus cineraceus Temminck, in winter. Evening roosting behabior and the dispersal at dawn to the feeding ground 5-6km. apart, the daytime feeding behavior and its change towards evening to flock on a large tree before leaving at sunset to the roost, are described. The bathing is preferably done in late afternoon.
2. Necessary factors for a feeding ground at paddies with some cultivated area, are: scattered trees to rest on, enough water, big trees or pines (at a private house or a local temple) to gather in the morning and evening, also abundance of food (use of much fertiliger) and least menace by people.
3. They breed scattered at suitable hollow trees within the feeding area. Quarrel was observed between pairs for a hollow and almost 1/4 of the flock seemed to have psychologically returned to non-breeding condition by lack of nesting cite. Before this, the birds which abandon the winter roost increased and they began to overnight at a small bamboo-grove within the feeding area (In another feeding area closer to the winter roost, such spring roost was lacking).
4. The main feeding area studied was north to 6.5km. from the winter roost, and was about 12 square km. within which 800-900 individuals were counted. This area can be sectioned into several subareas different in feeding population, from almost 0 to 3 birds per 100 meter square, by difference of surroundine factors. At 14km, from the winter roost was found a feeding ground of another population. (see next issue for Japanese original)
5. Though often overlooked by some farmers, value of starlings as winter protector of paddies from noxious insects and the larvae and also as eliminators of flies growing from the fertilizer, is to be further studied.
6. Summer to autumnal change of the flock's behavior will be described in the next report.

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脉翅目のヒメカゲロウ上科の染色体研究を行った。調査した種類は,ヒメカゲロウ科の6種と,クサカゲロウ科の7種である。全種類共,性決定様式はX-Y,X-X型で,X-,Y-染色体は第一成熟分裂で著明な先行現象を示している。
ヒメカゲロウ科の中,ヒメカゲロウ亜科の今迄に調査された5種と今回の2種の2n=14であるが,ヤマトヒメカゲロウだけが2n=16であった。Microminaeの2n=12と16で,この亜科については基礎数が決まっていないようである。
クサカゲロウ科の染色体数から系統を考えると,以前のように属をクサカゲロウ属,ニネタ属およびクリソトロピア属とに分けたほうがよく一致するように思われる。

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脉翅目のウスバカゲロウ上科に属するウスバカゲロウ科の6種とツノトンボ科の1種の染色体研究を行った。
ウスバカゲロウ科のDendroleoninaeに属するものは全部2n=18であるが,ウスバカゲロウ亜科に属する昆虫の基礎数は2n=12,14および16と種々である。ウスバカゲロウでは所謂V形中心体が観察された。
ツノトンボ科のツノトンボの卵原細胞の染色体数は22個で,已に報告されている結果を裏付けすることが出来た。
この上科に属する昆虫も全部性決定様式は雄がヘテロで,雌がホモである。また性染色体は第一精母細胞の分裂で著しい先行分離を行っている。

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The crocodilians are not the Japanese animals but formerly they were included in the fauna of our country as the estuarine crocodiles live in Palao Islands, Micronesia which were at that time under Japanese Mandate.
I found three examples, old and new, among the literature about the crocodiles which were found drifting in the neighbouring sea of Japan but the reason why they drifted this far is unknown.
The first crocodile was caught in 1744 off the coast of Iwojima I., Kagoshima Pref. It was presented to the then Feudal Lord Shimazu, the head of Satsuma clan. This was presumably an estuarine crocodile.
The second one was a crocodile caught at Amami-Oshima I., Kagoshima Pref. in February 1800. There exists a color painting of this crocodile made at that time from which I can clearly identify it as an estuarine crocodile.
The third one was caught in a fishing net off the Toyama Bay, Toyama Pref. in November 1932. This was perhaps the same species.
No live crocodilians were introduced in this country before the Meiji Era. But during the Taishô and Shôwa Era crocodiles, alligators and gavials were brought in one after the other to the zoo of Japan.

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アブラコウモリの幼獣は成獣が多く発見されているに拘らず非常に少い。即ち今泉氏の「日本哺乳動物図説」に依れば3仔の場合は羽田1例,赤羽1例,名古屋2例,支那1例,2仔は鹿児島,1仔の例は奄美大島等である。随つて4仔は未だ知られていないように思われる。ここに述べた4仔の例は甲府市高畑町に母親に抱かれたまゝ墜落したもので之を1週間飼育したのである。
本種は山梨に於ては4月に最も多く出現し10月が之に次いでいる。従来日中に於ける発見は何時でも1匹のみの飛翔である。又この種の冬眠は家の中であるが,コウモリ穴の岩穴の1例もある事を附加し又ダバオに於て本種観察中多数のホタルを食したが,それらの発光部のみを残した事も食性上興味あることとして附け加えて置く。

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