IL THE CONCATENATION HYPOPHYSISr->OVARY 

 -^.OVIPOSITOR IN THE BITTERLING 



§ I. THE HISTO-PHYSIOLOGICAL EXAJMINATION 

 OF THE HYPOPHYSIS 



As we observed, it is possible to induce growth of the ovipo- 

 sitor in the female bitterling by the administration of estro^ 

 genie (mammalian) hormones. Further investigation showed 

 that the reaction of the ovipositor takes place not only after 

 administration of estrone, but also after administration of 

 progesterone, testosterone and desoxycorticosterone; in short, 

 all estranes, pregnanes, and androstanes. 



As injection of an aqueous extract of the hypophysis of 

 the carp caused marked formation of corpora lutea as well as 

 growth of the ovipositor in the female bitterling, we suspect- 

 ed that this growth might be regulated by the hypophysis, 

 through the corpora lutea. The latter will be dealt with in 

 greater detail later. The possible role of the hypophysis was 

 investigated ( i ) by a histological and cytological study of 

 the hypophysis and by observation of the changes occurring 

 simultaneously in the ovary and in the ovipositor, and (2) 

 by noting the effect of hypophysectomy.i 



^VAN OORDT and BrETSCHNEIDER investigated the possibility of devel- 

 oping premature sexual maturaty in sexually immature eels (Anguillae 

 from 30-37,5 cm long, abt. ^}/2 — 8 years old) by administering gonad- 

 otrophes. To this end they used Ambinon "Organon", which consists 

 of an extract of the anterior mammalian pituitary, in combination with 

 Pregnyl "Organon", i.e., an extract from the urine of pregnant women 

 and the pituitary sap of sexually mature, spawning carps, the hypophyses 

 weighing together 1 3^2 g- It was shown that the infantile testis of the eel 

 is thereby stimulated to form spermids after the administration of an 

 extract of 2-6 carps' pituitaries, and also by 2000 I.U. Pregnyl combined 

 with 400 I.U. Ambion. Only an unphysiologically high dose of mam- 

 malian hormone, therefore, can have effect on the eel. This proves once 

 again that, in investigating the endocrinology of non-mammalian verte- 

 brates, it is preferable to use hormones which are specific to the species 

 investigated. 



