作者: MARGARET HILL
DOI: 10.1111/J.1096-3642.1939.TB00724.X
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摘要: Summary Three hundred and twenty-seven male weasels were collected in England Wales during 1931 to 1935. They have been used study the limits of breeding season, seasonal changes undergone by reproductive organs, development organs young animal. The structure is simple, being similar those ferret stoat. There are no seminal vesicles obvious prostate gland. The testes descend at an early age remain scrotum throughout life. In skull, jaw, teeth, os penis, weasel reaches about six seven months a condition indistinguishable from that adult animal. One thirty-four classified as animals one sixty-six adults older. The born over extensive period, April possibly late September. Males May, reach body weight very quickly, become sexually mature when four old. Sperms present most advanced towards end July August. Such weigh 0–107-0-222 gm. Young males later season do not attain sexual maturity until year following which they born. Their rate growth generally so rapid, September their less than 0–09 Arrest regression begin beginning of-October. By December all reached ancestrous quiescence. At there difference time taken arrive spermatogenesis between previous group animals, both active March. The points its first life noted:– 1. testis more closely correlated with tubule diameter it adult. 2. After maximum seminiferous has continued lengthening tubules increase weight. 3. Both absolute epididymis relative adult. 4. interstitial cells smaller normal adult. 5. During winter two types can be separated histologically–those resemble belong young. The (animals months) fully March August, signs apparent, though fertile found February 17th middle October, showing may occur period eight months. Retrogression comparative quiescence October lasts next year. From January preparing actively for onset perhaps even rapid regression. At does production spermatogonia spermatocytes cease entirely. Ancestrous therefore slightly marked It thus appears anterior pituitary gland partially winter, hedgehog, least three rows winter. Seasonal variation size quite great ferret, correspondingly change tubule. There definite cycle cells. large average cell area 180 250 sq. p, whilst small crowded together non-breeding 80–90 μ. The related testis. The vas deferens shows cyclic activity testis. This work was begun my tenure Keddey Fletcher-Warr Studentship University London. I wish express grateful thanks Sir Henry Dale, F.R.S., providing me facilities National Institute Medical Research, Dr. A. S. Parkes, use material, reading paper, much helpful criticism. I am also indebted Professor F. W. Rogers Brambell his generous assistance collecting Mr. J. Thornton Carter kind help working out dentitional characters skulls, Matthew advice on statistical treatment certain data. I thank H. B. de Montmorency pointing significance distortion frontal ethmoid bones many skulls. The photo-micrographs Pittock, whom cordial due.