PAA Be eXole 
CorLtorocrras, EuLopHocERAS, MrrToicocERAs. 
Section same as Pl. X, fig. 6, enlarged. 
NIG S42 OaeNeL UO DROCERASHLOLCLET SC ploy atl te a ese eae ae 86 
Fig. 2. Side taken before specimen was ground to show section. 
3. Section somewhat more than natural size, and somewhat restored, shows 
the umbilicus on the right completely filled by the shell layers. This 
filling occurs in the adolescent stage, inclosing the dark spots on both 
sides of the center, which indicate that the shell did not fill the umbilici 
at an earlier stage. 
4. Enlarged view of center restored. 
5, 6. Shows keel to have been solid at this age. 
6a. Enlarged drawing of hollow keel of venter connected by a dotted line. 
Natal, South Africa; Cretaceous; Yale Museum. 
hes, (Os Wigner Senallond (SowwTe Wl) = 352 be ced eebaeceuasadaccsuocessesscausndasoeose 118 
Fig. 7. Protoconch and part of nepionic volution, 56+, actual transverse 
diameter 3/10 mm. 
8. Side view of same, showing the abrupt bend in the protoconch before the 
nepionic tube began to be formed, and the first two sutures. 
. Optical section of same along dotted line in fig. 8 and from front of view 
shown by the arrow. 
10. Front view of the specimen before removal of the outer volution, x 36. 
11. Enlarged view of the czecum and first section of siphuncle, showing also 
the ventral lobe divided by a siphonal saddle. 
12,13. Neanic stage, showing the aspidoceran-like form and tubercles, < 6. 
14,15. A little older stage with living chamber complete at the umbilical 
shoulder, over 1/2 volution in length, * 6. Back of this shows rounded 
venter of the neanic stage just becoming divided by the incoming of two 
rows of tubercles. 
16,17. Early ephebic substage. 
18. Sutures of fig. 12 about first quarter of fourth volution, « 12. 
19. Suture of second quarter of same volution. 
20. Suture of probably fourth quarter of same volution. 
21. Dorsal suture of the second volution, x 12. 
22. Dorsal suture of what was considered to be the last of fifth or part of sixth 
volution, < 12. 
23. Dorsal suture later in age than fig. 22, « 12, of same age as suture Pl. XIII, 
fig. 1. 
24. Lateral suture of fig. 16 enlarged 3 diameters. The ventral lobe has been 
distorted by setting the siphonal saddle at an eccentric angle. 
Texas; Colorado epoch; my collection. 
See P]. XIII for other figures of this species. 
We) 
