150 PSEUDOCERATITES OF THE CRETACEOUS. 
Sutures are considerably worn, except in one place at diameter of 75 mm., 
the volution being 23 mm. ventro-dorsal diameter. These were similar to 
those of the typical specimens, except the first lateral saddles, which were 
narrower and distinctly bifid; the innermost inflections were not seen. 
The nodes were present on the umbilical shoulders, but apparently 
disappear on the last half of the outer volution, but this could not be 
proved on account of the state of this fossil. 
The venter remained concave to the end. The ventral tubercles 
became, however, much finer and more closely set than in the ephebic 
stage, and I should think more perfect specimens might show the 
correlative disappearance or obsolescence of the costations. I doubt if the 
coste are ever so broad in this species as in syriacum. The state of these 
fossil casts tends to confirm the opinion that they were not living members 
of the fauna with which they were found. 
Out of the eight casts in the Museum of Comparative Zoology only 
three were suitable for observation, and all of the three more or less 
imperfect, and there was not even the minutest piece of a shell on any of 
them. The same is also true of the large specimen from the collection of 
Columbia University. 
KKNEMICERAS COMPRESSUM var. SUBCOMPRESSUM Hyatt. 
Pl. XVI, figs. 11-14, 19. 
Amm. syriacus (pars) von Buch, Abhandl. K. Acad. Wiss. zu Berlin, 1848 (not 
figured). 
Amm. syriacus (pars) Conrad, Lynch’s Exp. Dead Sea and Jordan, 1852, pl. 14, fig. 
74, two upper figures (not fig. 6). 
This variety has heretofore been confounded with nem. syriacum, 
from which it is, however, easily separated. The form even in extreme age 
is more compressed, the nodes on the umbilical shoulders are not so promi- 
nent, and the venter and transverse diameters do not broaden out in the 
later ephebic and gerontic substages, as in that species; the nodes also on 
the edges of the venter are longer and narrower than in that species. The 
sutures are very similar in these two forms. 
A specimen from Mukhtara, Syria, in the American Museum of 
Natural History, New York, reaches 97 mm. diameter without living cham- 
ber, and shows that the shell sometimes reaches a larger size than 115 mm. 
in diameter. 
