368 J. M. Safford on the Cretaceous 
3. Crassatella pteropsis, Gabb, - : - - ab, 
(Conrad had previously given this name toa species of Crassatella; 
Jour. iv, 279. I therefore propose C. Gabbi for it.) . 
4. C. Monmouthensis ? Gabb, - ee 
6. Cardita subquadrata? Gabb, - - - - b 
6. Leda nrotexta, Gabb, - - - : - b, 
1. Modiola Saffordi, Gabb, - ‘ : nce ae a 
8. Ostrea denticulifera, Con., - - - er * 
9. O. crenulimarginata, Gabb, - - - : 6, 
(If No. 8 is referred to the proper species, then O, crenulimargin- 
ata, Gabb, is, I think, its lower or larger valve.) 
10. Grypheaa Vomer, Mort., - : 
11. Turritella Tennesseensis, Gabb, - - f 7. 
12. 7. Saffordi, Gabb, - . - - - 
1 } - 
Pe ae 
14, 7. pumila, Gabb, = as 
15. Nutica rectilabrum, Con., - 
sciola 
17. Neptunea impressa, Gabb, - 
18. Callianassa ? Gwyni, Safford, - © * . 
19. Lamna gracilis? Ag,  - 
20. Crocodilus ? (Tooth.) 
It will be seen that but two species of those given, Gryphea 
Vomer and Natica rectilabrum, are common to this group and the 
Greén sand. Localities in Mississippi, however, furnish series 
of fossils which unite the groups more intimately. It will be 
found perhaps that the two form paleontologically but one 
SASS KCTS SSP 
€. ge He ee 
F 
formation 
The group also contains wood and leaves. The leaves are 
generally found in an imperfect condition and have received but 
ittle attention. As the age of the beds containing them are 
nown, their study would be ver interesting in connection with 
that of the leaves of the formations further west which are 
ica 
scales, is dark when wet and whitish grey whendry. The thick 
ness of the series is perhaps 200 or 800 feet. In this are usually 
several beds of slaty clay from five to fifty feet in thickness. 
Hardeman county, on Porter's Creek,* is a heavy bed said a 
00 feet thick. Ihave seen as much as 50 or 60 feet of it exp 
" The first creek on the map, west of “M.” (Middleton,) on the M.& ©. R. BR 
