PLATE XXXV. 
PAGE 
Pigs. 1-10 Cythere clarkaxa n. sp 9S 
1. Rather short left valve. Plum Point. U. S. Nat. Museum. 
2. A left valve of the average length and dimensions. Same locality. 
3. Unusually elongate right valve. Same locality. 
4. Rather short right valve, without spines on either end. Same 
• locality. 
5. Dorsal view of a large specimen. Same. 
6. Right side of entire carapace differing slightly in outline from 
the usual form. 
7. Dorsal view of another specimen. 
S. Ventral view of a specimen, broken to show overlap of edges. 
9. A small and somewhat macerated left valve. 
10. Interior of a short right valve. 
Pigs. 11-14. Cytheke claskana var. mi.nuscula n. var 99 
11, 12. Two left valves of this variety. 
13. A right valve, somewhat doubtfully referred to this variety. 
14. Interior of the largest left valve seen. 
Figs. 15-17. Cytheke ix.icquivalvis n. sp 101 
15. The left or larger valve. Plum Point. 
IC. The smaller and quite differently shaped right valve, Same 
locality. 
17. Interior of another right valve. 
Pigs. 18, 19. Cythere plebeia var. modica n. var 103 
IS, 19. Two left valves of this variety differing somewhat in outline. 
Plum Point. 
Pigs. 20-29. Cythere plebeia n. sp 102 
20. Ventral view of two valves partly opened. 
21. Right side of an entire carapace of average form and dimen- 
sions, showing inequality of valves. 
22. Left valve of the usual form. 
23-25. Three entire specimens figured to show respectively dorsal. 
ventral and dorsal edges. 
26, 27. Two views of an unusually wide left valve. 
28. A similar left valve having a well developed border along the 
anterior edge. 
29. Interior of another left valve like Pig. 28. 
Pigs. 30-33. Cytheke plebeia var. c.apax n. var 103 
Left valve of this variety, showing relatively shorter form and 
finer surface punctation that distinguishes it from the 
typical variety of the species. Plum Point. 
Two right valves. Plum Point. 
Interior of another right valve. Plum Point. 
The figures on this plate are all magnified 20 diameters and the specimens 
are all from the Calvert formation at Plum Point, Md. 
:s. 3 
0-33, 
30. 
31, 
32. 
33. 
27 
