No. 9.— CONTRIBUTIONS FROM THE ZOOLOGICAL LABORATORY 

 OF THE MUSEUM OF COMPARATIVE ZOOLOGY AT HARVARD 

 COLLEGE. E. L. Mark, Director, No. 230. 



On the hair-lihc appendages in the frog Adylostcrnus robusfus (Blgr.). 



By Willy Kukenthal. 



While working at the Museum of Comparative Zoology at Harvard 

 University, soon after my arrival in Cambridge, Dr. Thomas Barbour 

 called my attention to some frogs collected in Kamerun. I was much 

 struck by their very peculiar appearance which showed a dense cover- 

 ing of hair-like filaments on both sides of the body and on the outer 

 surface of the thigh (Plates 1-3). 



This frog was described by Boulenger (:00, p. 443, pi. XXX), 

 who named it Trichobatrachus robustus, thus establishing, not only 

 a new species, but also a new genus. Boulenger pointed out that 

 the villose dermal papillae covering some parts of the body are far 

 from being a nuptial attribute of the males, as one might have been 

 inclined to suppose from analogy with various fishes, and he empha- 

 sized the fact that this character is more strongly developed in the 

 female than in the male. He suspected, therefore, that these hair- 

 like appendages are a mere seasonal peculiarity. About a year later 

 Boulenger (:02) published another short paper upon the same sub- 

 ject, having meantime had the opportunity of investigating seven more 

 specimens besides the two he had at first. He refers to an examina- 

 tion of the histological structure of the hair-like appendages made by 

 Dr. H. Gadow (:00) and confirms Gadow's view that we possess no 

 clue whatever to their physiological signification. Five out of the 

 seven specimens were adults. Of these five adults, three were females. 

 Although evidently obtained during the breeding season, these females 

 showed no trace of the appendages, whilst the two males had them very 

 well developed. 



We see that this statement is quite contradictory to that which 

 Boulenger had made in his first publication, but, strangely, the author 

 gi\-es no explanation of this discrepancy. 



In Gadow's short communication about the histological structure 

 of these peculiar villosities, he tells us that males and females possess 

 on their flanks, as well as on the upper and hind surfaces of the thighs. 



