144 BULLETIN 103, UNITED STATES NATIONAL MUSEUM. 



mm.; greatest height (proximally) , 15.3 mm.; least height (distally), 

 13.3 mm. 



Paratypes. — (a) One left propodus with about half of the fixed 

 finger attached was taken in the lignitic layers, about 65 feet below 

 the base of the Pecten bed at Tower N., Las Cascadas section, Gail- 

 lard Cut; central part of Culebra formation, Oligocene series; Prof. 

 W. B. Scott, collector; 1911 (Mus. Acad. Nat. Sci. Philadelphia). 

 The specimen is half embedded in a nodule which conceals the inner 

 surface and the upper part of the outer surface. It is nearly as large 

 as the type. It shows the large tooth at the proximal end of the pre- 

 hensile edge of the fixed finger, the tubercle on the outer surface near 

 the sinus between the fingers, and roughly, the ornamentation on the 

 lower edge of the palm. 



(b) From the same source, a similar left propodus half embedded 

 in a nodule but so as to expose the inner surface and the upper edge; 

 it shows the characteristic row of pits on the inner surface just below 

 the upper edge, the row sloping downward distally. 



(c) Also a third specimen, free from the matrix but with the edges 

 broken ; it shows the palmar ridge leading to the fixed finger and the 

 basal tooth on the edge of the latter. 



CALLIANASSA TENUIS, new species. 



Plate 60, figs. 13 and 14. 



Type-locality.— Panama Canal Zone. Las Cascadas section, Gail- 

 lard Cut. From fifth or topmost limestone. Emperador limestone. 

 Oligocene series. D. F. MacDonald and T. W. Vaughan, collectors, 

 1911. Station 6019#. 



Holotype.— Cat. No. 324282, U.S.N.M. Left manus with propodal 

 linger broken off, segment shorter than its greatest height, in general 

 subrect angular, with upper and lower margins converging distally; 

 outer surface very convex from top to bottom; upper and lower 

 edges marginate, the lower one very thin; inner surface convex ex- 

 cept near the bottom where it is flat, at the proximal end where there 

 is a furrow parallel with the articulation, and near the distal sinus 

 where there is a depression. The propodal finger is very much 

 smaller than the dactylus, and its cross section is suboval with 

 pointed ends ; the sinus is about as wide as the thumb ; it bears, close 

 up to the insertion of the dactylus and on the edge of the outer sur- 

 face, pointing forward, a short, broadly triangular spine. Surfaces 

 much worn, so that it is difficult to tell whether unevennesses are 

 natural or not. 



Measurements. — Length of manus, measured to sinus, 11.4 mm.; 

 greatest height, 13 mm. ; distal height, 10.3 mm. ; thickness, 5.3 mm. 



