PLATE XV. 
yvenus—Limopsis, Sasso. 
Fias. 
1—4. LL. albiensis, Woods. Gault, Folkestone. (P. 71.) 
1. Zone in. Lett valve. Museum of Practical Geology. a, outline; b, dorsal out- 
line ; c, exterior x 3; d, interior x 4. 
2. Zone vii. Right valve x 4. Same museum. 
3. Right valve x 3. Same museum. 
4. Zone ii. Part near umbo x 8. Same museum, 
5,6. L.,sp. Chalk Rock (Reussianwm zone), Cuckhamsley. Montagu Smith 
Collection, Woodwardian Museum. (P. 72.) 
5. Cast of interior of right valve, a, outline; b, dorsal outline; c, same x 2 
6. Cast of interior of left valve. a, outline; 6b, dorsal outline; c, same x 2. 
Genus—Myrtitus, Linneus. 
7. M. inequivalvis, Sow. Greensand, Blackdown. The Type. Bristol 
Museum. a, right valve; 5, left; c, antero-ventral; d, interior 
of right valve near the umbo x 2. (P. 91.) 
Genus—MoptoLa, Lamarck. 
8—14. M. xqualis, Sow. Crackers, Atherfield. (P. 92.) 
8. Leckenby Collection, Woodwardian Museum. a, right valve, outline; b, same 
x 14; ¢, dorsal of both valves. 
9. Wiltshire Collection, Woodwardian Museum. Right valve. 
10. Same Collection. Dorsal. 
11—13. Same Collection. 11, left valve; 12, right valve (slightly crushed dorso- 
ventrally) ; 13, left valve 
14. Woodwardian Museum. Right valve. 
15—18. M. reversa, Sow. Greensand, Blackdown. (P. 94.) 
15. Wiltshire Collection. Right valve, young form. 
16. Wiltshire Collection. Left valve, young form. 
17. Wiltshire Collection. a, right valve; b, dorsal outline of same. 
18. Woodwardian Museum. a, left valve; b, dorsal of same; c, portion just posterior 
to middle of the sulcus, showing radial ribs x 3. 
