194 Dr. H. F. E. Jnngcrsen on the Stmcture 



{Pipa and Xenopus) we find two neighbouring fingers with 

 two phalanges, the two others with three, a fact easily seen 

 on bending the fingers in any specimen preserved in spirit : 

 but whether the two-articulated fingers really are the inner 

 ones as in Phaneroglossa may seem open to doubt if the 

 examination is confined to the exterior alone ; closer exami- 

 nation of the skeleton will, however, soon dispel any 

 doubt. 



PiPA. 



The coalescence of the bones of the forearm in this genus is 

 more complete than in other Anurans, but still the position of 

 radius and ulna is easily distinguished, and so it will be seen 

 that the three-articulated fingers really belong to the ulnar side. 

 The lower end of the radius is broader than the corresponding 

 end of the ulna, and provided with an expansion of the inner 

 edge ; tlie whole forearm is strongly compressed, with sharp 

 ulnar and radial edges, its lower end being strongly concave 

 behind and rather convex in front. 



The carpus has all its constituents ossified, but the inter- 

 spaces between some of the pieces are filled with connective 

 tissue. In the proximal series it contains two bones of very 

 diflferent size. The ulnar (figs. 1, 2, and 4, w+Cg) is by far 

 the greater of all the carpal bones : proximally it carries 

 a large articular surface for the ulna and also another 

 smaller, but still considerable, for a part of the radius ; 

 distally it is provided on the outer side with a rounded liead 

 for the metacarpale V, and consequently it extends through the 

 whole carpus ; towards its inner (medial) side are two converg- 

 ing articular faces — one superior, smaller, for the radial piece, 

 the other inferior, larger, for the carpal bone (C + Cg). The 

 fore side is concave, but rises towards the outer edge, nearly 

 opposite to the groove that separates the ulna and the radius, 

 into a large process (tr), in which some of the muscles of the 

 arm are inserted, and muscles for the dorsal flexion of the fingers 

 take their origin ; on the hinder face the bone in question is 

 also concave, and is here, under the sharp edge of the ulna, 

 provided with a heel-shaped process (?/), smaller and in a 



Proc. Zool. Soc. 1888, p. 204) has shown that the genera Cassina, Gir., 

 HyJamhntes, A. Diini., Rappia, Gthr., Mcgnlixalus, Gthr., Rhacophorus, 

 Kiihl, Chiromantis, Peters, Lralus, Tsch., and Nyctiralus, Bouleng., have 

 a small bone intercalaled between the outermost phalange and that which 

 otherwise is the penultimate, so that the fingers are provided with 3, 3 4, 4 

 (and the toes with 3, 3, 4, 5, 4) phalanges. 



