The Embryonic Development of the Ovary and Testis of the Mammals  (English, Paperback, Allen Bennet Mills)

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: The two forms studied—rabbit and pig—are complementary in their points of special suitability for this work. Although there are minor differences in the development of the sex glands in these two forms, yet the general process is essentially the same. In general the pig is the more instructive form for a study of the early stages of embryonic development, while the rabbit furnishes material better suited for the study of the post-embryonic stages. The following tables indicate the stages studied, the sex of the specimen and the number of series cut in each case. The stage of development is indicated in the rabbit by the number of days and in the pig by the length of the embryo. f 13 D.i 140bD OS16 D.CO17D.018 D."a 19 D.o tf 21 D.123 D.25 D.1 26 D .Rabbit. Indifferent. 1 Female. Male. At Birth. Indlf- Stages. ferent. Female.I'm: Embrtos. 0.6 (cm. 1 0.7 cm. 1 0.8cm. 1 0.9cm. 1 1cm. 1 1.1cm. 1 1.25cm. 1 1.33cm. 1 1.4cm. 4 1.6cm. 2 l.flcm. 2 1.7cm. 4 1.8cm.3a.s cm.28cm.38.5cm.14cm.25cm.25.7cm.27.5cm.18cm.18.5cm.310cm.213cm.113.5cm.115cm.118cm.1.JOcm.125cm.1Male. 3 D. 8 D. 10 D. 13 D. 17 D. 34 D. 25 D. 31 D. 37 D. 45 D. 50 D. 78 D. 85 D. 93 D. 100 D. 130 D. [ 140 D. One each of the following stages of adult rabbit ovaries: 6-months-old virgin. Old Individual, 3 months since last pregnancy. 3% days pregnant. 3% 16 17 23 During lactation. 1st pregnancy. Note—The pig embryos were measured from the cervical to the tail bend in all stages up to 5 cm. length, when the measurement was taken from the base of the tail to the top of the head. This change was made for practical reasons of precision. The 5 cm. stage would be about equivalent to the 4 cm. stage. The material was, in practically all cases, fixe...