1' I. A 'IM-: i> 1 1 I . 



(^lATlCKXAUY 1'K('TP:NS. 



|Unli'-is iilliiTwisi' sliitid all lii,'ur.s an- ii|i|inixii]iHlc'ly iiiitunil size.] 



Page 



Fui. 1. I'idni (.V..i/(/»r/,;,) ,v»/„i«»/,«».v Sdwerliy. I,. S. .1. 1' ll'S 



ExtcriDi- of left v;ilve; altitude 111' iiiiii. Urci'iit, wi/st coai-t (jf Mexicii. (M. K. ) 



Fio. la. Same sprciiiii-ii a.< tli;. 1 I-i^ 



Pnitile nf lidtli valves as viewed fmm the fear. (M. P.) 



Fici. ■_'. fn-l,;i {l'i-n,„;nnnxiiim) ahiskeii.fix Dall. U. S. N. M. 149604 V.Vi 



Exterior of ri^lit valve; altitude 1'2 mm. lleeeiit, .southwest of I'riliilnf Islamls, I'.eriujj; 

 Sea, SO fathoms. (U. K. Fish Com. statiou :W02. ) (S. ) 



Fio. '2<i. Same speeimeu as fijr. 2 l'^-'5 



Exterior of left valve; altitude -■') mm. (Note differenee iu size of right and left valves 

 of same indi\ idual. I (S.) 



Fic;. S. /'(■(•/(•/; ( J'mpoimuxiKiii ) dliiskciisix Dall. V. S. \. M. C.L'.'U:; 138 



Interior of slightly imiierfeet U'ft valve, shuwiiij,' internal riblets; altitude I'll nun. 

 Recent. Pnint Etehes, Alaska. (S. ) 



250 



