PLATE XXXII. 
Prcren (continued). 
Fies. 
1—3. P. (Chlamys) clongatus, Lam. (P. 170.) 
1. Grey Chalk, Dover. York Museum. a, right valve; 6, portion of the same near 
the middle of the valve x 3. 
. Lower Chalk, Burwell. Woodwardian Museum. a, left valve; 6, part of the 
same near the middle of the valve x 3. 
3. Same horizon, ete. a, right valve; b, part of same below the middle of the 
valve xX 3. (The anterior ear is displaced.) 
bo 
4—6. P. (Chlamys) cretosus, Defr. A. quadratus zone, East Harnham. Dr. 
Blackmore’s Collection. (P. 174.) 
4a, left valve x li. 
4b, mid-ventral ribs of 4a x 3. 
4c, right valve of the same specimen x 13. 
4d, mid-ventral ribs of 4¢ x 3. 
5a, left valve. 
5b, part of 5a posterior to the middle of the ventral border x 4. 
6a, left valve. 
6b, umbo of 6a x 3. 
6c, part of 6a near the mid-ventral border x 4. 
