PLATE I. 
Fig. 1. Corbula Krebsiana C. B. Adams; 6.1. Page 315. 
6c 1 a. ee “ce 
ce if b. ce ‘ce 
« 2.  Basterotia quadrata Hinds; 10.0; left valve. Page 3816. 
« 2a. Same, hinge seen from above. 
eo OND aes be “ below. 
« 8. Corbula Knoxiana C. B. Adams; 12.7; front. Page 318. 
aS SoBe es = back of left valve. 
“ce 3 b. “c “cc 
“ce c. is3 oe 
“ 4,  Corbula disparilis D’Orbigny ; 9.0. Page 314. 
“e 4 a. “ec “ 
“ce 4 b. ee “ce 
“5.  Corbula Dietziana C. B. Adams; 10.7. Page 314. 
ce 5 a. “ “ec 
“cc 5 b. “e 6c 
“ 6.  Corbula Kjoeriana C. B. Adams; 12. Page 316. 
6c 6 a. “ce 6c 
“ce 6 b. 6c se 
“ 7.  Corbula cymella Dall; 13.5. Page 315. 
“cc 7 a. “ce “c 
All the above, except figures 2 a,2b, and 4,4 .a,4b, are drawn from typical 
specimens of the describer. 
