COMPARATIVE PHYSIOLOGY OF THE VERTEBRATE HYPOPHYSIS (ANTERIOR AND INTERMEDIATE LOBES)

Abstract

Morphologically, a hypophyseal gland is found the oviducts remain rudimentary and non-func-in all vertebrates. It seems not unlikely that it tional. Injection of pregnant mare serum does has its homologue in some invertebrates also. A not repair this damage (unpublished tests by pouch forming in the roof plate of the mouth of Weed and Witschi). metamorphosing larvae of Balanoglossus resem- Table I gives a survey of "hypophyseal hor-bles closely the early stage of the hypophysis of mones " found in different taxonomic groups. It vertebrates, commonly called Rathke's pouch. The is based on original research as welI as on a con-"hypophyseal canal " of ascidian larvae which gives servative analysis of a very large literature which rise to the "subneural gland " of the adult has cannot be discussed here in detail. In spite of the been compared with the hypophysis of the verte- incompleteness of the information at the present brates. Abramowitz (1936) has extracted from time, one can safely conclude that a chromato-this organ a chromatophorotropic hormone which phorotropic principle and at least one gonadotro-physiologically resembles the pigmentary hor- pic principle are elaborated in the hypophyses of mones of the intermediate lobe of mammalian all vertebrates. Evidence of the presence of most hypophyses, as well as those extracted from eye of the other principles has been found in amphi-