204 Dr. II. F. E. Junj;crscn on the Structure 



Xenopus. 



Tlie structure of the hand in tills genus is mentioned by but 

 few authors. Mayer (' Analecten,' 1835, p. 34) simply says 

 about A", kevis (Daud.) " Der Carpus besteht aus fiinf bis 

 scclis kleinen Knochelchen," and makes no remarks concerning 

 the skeleton of the fingers. The accompanying figure of the 

 whole skeleton in his work (which is with some additions due 

 to Schlegel) is rather incorrect both as regards the carpus and 

 the fingers, the latter being assigned the following number of 

 joints, 2, 3, 3, 2. From the relative length of the fingers and 

 from tiie description of the exterior of the animal {cf. I. c. tab. ii. 

 fig. V.) it is evident that tlie hand is turned with the inner 

 side outwards and the palm looking upwards. Mayer says 

 (/. c. p. 29), " Es sind vier Finger vorhanden, wo von der 

 zweite innere um cine halbe Linie liinger ist als die iibrigen ; " 

 in reality this applies to the penultimate finger. Hallowcdl *, 

 in his description of Xenopus [Dactylethra) MiiUeri, Peters, 

 says, "... fourth finger stoutest, second lonrjest^ first and 

 fourth of nearly equal length ;" thus he falls into the same 

 error as Mayer. A. Dunieril "j" figures the hand correctly in 

 X. ccdcaratus, Peters ; but as the text is no improvement 

 on Ilallowcll's description of the fingers in A". MiiUeri, with 

 w liicli Uumeril holds his species to be identical, the correctness 

 of the figure is apparently due to the artist. Peters +, in 

 his diagnosis of the genus Xenopus, rightly observes " Die 

 Zahl der Piialangen der Finger 2, 2, 3, 3 und der Zelien 

 2, 2, 3, 4, 3 ist die gewohnliche; '' but in the beautiful pictures 

 of his A". MiiUeri [L c. tab. xxv.) he still depicts the lower 

 side of the hand in that figure which represents the animal 

 seen from above (fig. 3), and the upper side of the hand in 

 fig. 3 a, representing the lower side of the animal. Howes 

 and llidewood {I. c. p. 163, pi. vii. fig. 4) have given the 

 first and hitherto only complete representation of tlie carpus 

 {X. kevis) ] but they have here made tiie same mistake as in 

 Pipa, figuring the right hand from behind, while they believe 

 they have represented the left hand from the dorsal side. This 

 is esjieeially evident from their referring to " the great exi)an- 

 sion of the head of the fourth metacarpal," a peculiar feature 



* "Notice of a Collection of lioptilos from the Gaboon Country, 

 "West Africa," Troc. Acad. Nat. Sci. I'hilad. 1857, t. ix. p. Oo. 



t " Reptiles et Poissons de rAlriquo occidontale," Arch, dii Mu-*ouiu 

 d'Jlist. nat. t. x. lSr)S-(il, p. -2M. 



I ' Keit;o nacli Mur-?aiiiliiiim-,' Zuol. iii. Auiphibiin, lSv?J, p. 180. 



