( 4 oo) 



luscan remains in this matrix on Chappaquidick * encouraged 

 me to hope that careful search might bring some specimens 

 to light which could be identified. A systematic exploration 

 of all exposures was therefore prosecuted ; hundreds of the 

 concretions and shaly fragments were broken open and crit- 

 ically examined and the result was a collection, not only of 

 molluscs but also of plant remains, a few of which were 

 found sufficiently well preserved for identification. 



(a) Molluscs. 



The molluscs as a whole are poor specimens and are not 

 satisfactory subjects from which to deduce any definite con- 

 clusions. They were first submitted to Professor R. P. 

 Whitfield, of the American Museum of Natural History, 

 who kindly examined them and from whose report upon them 

 I quote as follows : 



" I have examined the fossils you sent the other day but I 

 cannot satisfy myself as to their age. They consist of a 

 Modiola, which apparently does not differ from our common 

 M. flicatula of the harbor here ; an Anomia which might pass 

 for A. argentaria of the lower greensand marls of New 

 Jersey, if it were not for the Modiola; also a single imper- 

 fect internal cast of a small (young?) Pectunculus — not enough 

 of it to tell the species — and a small bivalve of which I can 

 not yet determine the genus. * * * These are the only shells 

 I can recognize and from their evidence I should think the 

 rocks could hardly prove to be Cretaceous." 



The same specimens were subsequently examined by Mr. 

 A. W. Grabau, of Columbia University, who identified the 

 Modiola as M. sulcata Lam., a species now living in the 

 Bahama Islands, and also noted a number of specimens of 

 Leda sp. ? 



In addition to the above there are a few coiled shells, one 

 of which is almost certainly referable to Ccrithium sp. ? of 

 Shaler's report (Bull. Mus. Comp. Zool., /. e. t ft- 2, fig. 12.) 



•Ann. Rept. U. S. Geo!. Surv. 7 : 341. 1888. 



Bull. Mus. Comp. Z06I. Harvard College, 16 : No. 5, 97. 1889. 



