1888.] THE CARPUS AND TARSUS OF THE ANURA. 157 



his deduction upon appearances presented to him in sections of two 

 " vierbeinigen Alyteslarven." On p. 158 will be found a full state- 

 ment of our reasons for refusing to accept the main observation upon 

 which this view it based ; consideration thereof will show that even 

 if that be reliable, there are still insufficient grounds for assuming 

 e vestiffio that the lunatum is the intermedium. 



When, to the above, we add that all attempts to discover at any 

 stage, in its proper place, a trace of a third proximal carpal element, 

 have failed us, there is nothing left us but to record our belief that 

 the lunatum represents the radiale alone, and that all traces of the 

 intermedium have vanished from even the ontogenetic record (c/. 

 hind foot, p. 145). 



f. Postaxial Gentrale (5th carpal of earlier observers.) {k). — 

 We have discussed this element sufficiently under the head of 

 "carpal 5 " (p. 154) to render further details needless. It is present 

 as a distinct element only in the lower families ; its great size and 

 comparative uniformity are its most striking features. If the mor- 

 phological value claimed by iis (p. 154) for that new element which 

 we interpret as the 5th carpal be accepted, this one, looked at from 

 all possible standpoints, can only represent a centrale. We proj)ose 

 therefore to term it, in accordance with its position, the postaxial 

 centrale, by way of distinction from the element next to be dealt 

 with. 



g. Naviculare (" scaphoide " of Duges) (?«.), — This element 

 is by far the most troublesome in the whole carpus, if not in carpus 

 and tarsus taken collectively. It may fuse with others in a manner 

 to be described later, but in all the lower representatives of the 

 Order it is permanently distinct. In position it is extremely variable, 

 except for the faet that it is preasial : in Leptodactylus (fig. 25) 

 and CeratopJirys, for example, it lies in the proximal row and arti- 

 culates directly upon the radius ; in the Biscoglossidce and Aglossa, 

 on the other hand, it is invariably central, being disposed, in the 

 former family, side by side with the postaxial centrale (figs. 4, 5, 

 and 7), with which it seems to vie in size. 



Born states (6, p. 62) that in the two " vierbeinigen Alyteslarven " 

 previously alluded to he found " inmitten des Carpus ein freies, 

 wohl abgegrenztes Knorpelchen von halbmondformiger Gestalt ; " he 

 regards this as the centrale, and adds " bei zwei anderen Carpen war 

 dasselbe mit carpale 5 verwachsen und bildete an demselben einen 

 deutlich abgesetzten, zungenformigen Fortsatz ? " He relied, as we 

 have before remarked, upon the section-cutter's method alone, and con- 

 sidering that he makes this " wichtige Fund " the basis of a revolu- 

 tionary redetermination of the morphological value of certain 

 leading constituents of the carpus (coming to regard the naviculare 

 as a displaced radiale, and the lunatum as the intermedium), he 

 ought, in justice to himself, to have given drawings of a complete 

 series of sections, in place of the solitary and somewhat diagrammatic 

 one proffered (pi. i. fig. 5). 



Bom's figure shows that ossification of the metacarpals had set in, 

 and, from the circumstances of the case, it is logical to expect that, if 



Proc. Zool. Soc— 1888, No. XII. 12 



