Prod. 



752 



Strophomena lima^ Jour. Ac. Nat. Sci. Phil. Vol. 8. p. 256 ; as- 

 sociated with P, lachrymosa^ and passing into it by variations 

 of form ; approaches P. hoydii^ by being distinctly depressed 

 in the middle, the dorsal valves being correspondingly elevated, 

 leaving a depression in interior casts, which are often the only 

 remains to be found in the rock ; but differs in the ventral valve 

 being more gibbous, in a depression broader and shallower, 

 and in the characteristics spiniferous tubercles. Various 

 places in western New York. (Hall.) — Chemimy. VIII g. 



Productella onusta, Hall. P^l. N. Y., Vol. 4, 1867, page 



HalLTaf.Ny. 



184, plate 26, figs. 29 to 42, from which I select a number. — Cht" 

 m.ung. — In Erie Co. Pa., collected b}'' I. C. White atLe Boeuff's 

 quarry, one mile from Le BoeufF RR. station, Spec. 869-17 I 

 (cast.) from Panama conglomerate. Also at Warren, Spec. 

 9485 of Randall's collection, from Upper Chemung. VIII g. 

 — Hall says this shell is very symmetrical and the largest 

 among the species of this subgenus, readily distinguished from 



