z6o 



THE QUARTERLY REVIEW OF BIOLOGY 



resemble those of other Anura, and a chart 

 built from his observations is herewith 

 presented. See Chart IV. 



Champy also reports that interstitial 

 tissue is abundant during winter in Rana 

 esculent a, Hyla arborea, Bufo calamita, B. 

 vulgaris, B. pantherina, and Alytes obstetri- 

 cans. Similarly he found that presperma- 

 togenesis takes place throughout the year 

 in each of these frogs and toads except 

 Alytes. 



Urodeles are much like anurans in 



the interstitial gland, but he adds that it 

 is difficult to admit that the interstitial 

 tissue is endocrine in function (8, p. z66) 

 because he was unable to find the supposed 

 relation between the development of 

 secondary sex characters and the develop- 

 ment of the interstitial tissue (p. Z70). 

 He therefore believes that in those anurans 

 having prespermatogenesis the hormone is 

 produced by this abortive spermatogene- 

 sis. Champy looks upon prespermato- 

 genesis, especially in urodeles, as a process 



JAN. FEB. MAR. APR. MAY JUNE JULY AUG. 5E.PT. OCT. NOV. DEC. 



CHAKTBT BUFO VULGARIS 

 -QUANTITY OF 5EERMATIC TI55UE, QUANTITY OF INTERSTITIAL TISSUE 



JAN. FEB. MAR. APR. MAY JUNE JULY AUG- SEPT. OCT NOV. DEC 



CHAKT3?. NECTURUS MACULOSUS 

 - QUANTITY OF 5PEKJ1AIIC TISSUE , QUANTITY OF INTER5TCTIAI. TISSUE T =KA3:iNG 



respect to testicular modifications. 

 Champy emphasizes this similarity, and 

 Chart V of Necturus maculosus, constructed 

 from Humphrey's data, shows that this is 

 true. Champy noted that in Salamandra 

 maculosa, S. atra, and Amblystoma tigrinum 

 interstitial cells appear after the sperma- 

 tozoa are expelled. When spermatogene- 

 sis takes place they degenerate. 



Champy places emphasis upon pre- 

 spermatogenesis, found in both anurans 

 and urodeles. He states that in anurans 

 this endocrine function is performed by 



of forming a "corpus jaune testkulaire," 

 which produces the hormone. He states | 

 (8), however, that these bodies develop ; 

 after the appearance of the secondary sex 

 characters. 



Humphrey (zi, zz, and Z3) has made a 

 very complete study of the interstitial 

 cells in urodeles. He reports that in 

 Necturus maculosus few or no spermatozoa 

 are present in the testis during the winter. 

 These entirely disappear from the testis 

 before the end of the following April. 

 Spermatogonia! division may be seen dur- 



