GEOLOGY AND PALEONTOLOGY OF THE CANAL ZONE. 139 



finger being the largest; there is also a medium-sized pit a little 

 below the middle, while 3 small ones are visible near the proximal 

 end. A prominent blunt ridge runs from near the top of the fixed 

 finger obliquely backward and upward for a short distance on the 

 palm; near this ridge, but chiefly above it, and partly behind it, 

 there is a patch of low tubercles, mostly oblong but very irregular 

 in shape and size. On the inner surface there is a row of 8 sockets 

 a little distance below the thin, upper, marginal rim; these sockets, 

 while of good size, have very narrow, perpendicular openings. Above 

 the lower margin there is a row of 12 sockets; this row distally ap- 

 proaches close to the edge, while the sockets themselves become larger 

 and farther apart; they are very oblique to the margin and are 

 almost more distal than lateral in their inclination. These 2 rows 

 of sockets on the inner surface are more prominent than any others ; 

 below the middle there are 10 or 12 scattered sockets mostly small; 

 near the middle there is a patch of tubercles, somewhat masked by 

 a thin layer of adhering matrix. On the inner surface there is a 

 blunt ridge leading back from the finger similarly placed to that on 

 the outer surface, but lower and wider. The finger is slender, judging 

 from the section at its base. 



Paratype. — This propodus shows the outline of the proximal end, 

 but the distal end is broken off and not a vestige of the finger remains. 

 The size is less than in the holotype : length, at the level of the sinus 

 between the fingers, 10.3 mm.; greatest height, 11.4 mm.; least 

 height, 10 mm. ; thickness, 5.2 mm. The margins are more con- 

 vergent than in the holotype and the palm is relatively shorter. The 

 upper as well as the lower edge is almost smooth. On the outer sur- 

 face the sockets in the upper submarginal row are 4, as there is an 

 additional one visible at the proximal end ; the sockets of the lower 

 row are fewer and more distant than in the larger specimen, as only 

 5 can be detected ; of the scattered sockets, 3 form a distal triangle, 

 while 10 or 12 small ones are disposed transversely near the proximal 

 end ; the protuberances above the oblique ridge leading from the fixed 

 finger consist of a few small granules. On the inner surface, a 

 row of 8 submarginal sockets above, as in the holotype; near the 

 lower margin only 10 sockets can be counted, because the distal 

 corner is broken away; scattered sockets 16 or 18, below the middle; 

 a few granules close to the sinus between the digits. 



CALLIANASSA ELONGATA, new species. 



Plate 60, figs. 4-6. 



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

 Gaillard Cut. From lowest fossiliferous bed, third bed below lowest 

 limestone beds separated by rows of nodules. Lower part of upper 

 8370°— 18— Bull. 103 10 



