Abstract
Ovulation in adult amphibians has been experimentally induced by hypophyseal transplants or by administration of extracts of the hypophysis in a number of species by various workers. Wolf 1 succeeded in producing ovulation out of season in frogs by means of homoplastic transplantation of anterior hypophysis. Houssay, Giusti, and Lascano-Gonzalez 2 and Houssay and Giusti 3 were able to bring about a similar response in toads by the use of homoplastic implantations of anterior lobe. The results obtained by Noble and Richards 4 on the salamander Eurycea bislineata, in which ovulation has been induced by means of homoplastic transplants, are confirmed by the findings of Adams 5 , 6 who was able to obtain egg-laying in adult Triturus viridescens and Triton cristatus by the same means. Similar results were observed by Adams 7 , 8 if heteroplastic transplants from anurans were substituted for the homoplastic implants. Adams 9 was also able to confirm the earlier findings of Houssay et al on ovulation in toads, in being able to elicit the response only with homoplastic transplants of anterior lobe substance.
Ovulation has likewise been produced in anuran amphibians with extracts of the mammalian hypophysis. Through the administration of an alkaline aqueous extract of the anterior lobe of cattle, Kehl 10 induced ovulation in the mature frog, Discoglossus pictus, and Adams 9 using a similar extract obtained the same response in frogs. Up to the present time there appears to be no record of ovulation in urodele amphibians produced by means of extracts of mammalian hypophysis.
Get full access to this article
View all access options for this article.