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S. W. WILLISTON. 



its matrix (Fig. 4). Because of the compression of the middle- 

 part of the carpus in our specimen, it is impossible to be quite sure 

 of the presence of both centralia. The radiale is much broader 

 than long, articulating with the radius, the distalia of the second 

 and third digits, and with one or possibly two centralia. The 

 ulnare is a much larger bone, articulating proximally with the ulna, 

 distally with the two inner distalia, and on the outer side with the. 



FIG. 3. Parioticlms laticeps. Photograph of right front foot, from thinner halfs 

 of nodule ; natural size. 



intermedium. That there is a free intermedium here as in Labido- 

 saurus is certain, but I cannot be quite sure of its extent, a part 

 of it being apparently covered over by the radius. It articulates, 

 as in Labidosaurns, proximally with the ulna and distally with a 

 centrale. Five digits are present, as was to be expected. The 

 first is represented by its metacarpal only, either slightly re- 

 moved from its articulation with the radiale, or, what is more 

 probable, with its distale lost, or cartilaginous. In the restora- 

 tion it is shown removed from the carpal bones as in the photo- 

 graph of the hand also given herewith (Fig. 3). The first 

 metacarpal is the shortest of the five, and is only moderately ex- 



