298 Doll — Miocene and Pliocene of Martha/ s Vineyard. 



Parts of the rock also contain numerous worn internal casts 

 of forarainifera which have been reconsolidated after wear. 



The shells are all represented by internal, or, in a few cases 

 by external casts, and in several instances the identification 

 though highly probable could not be made positive for want of 

 the external characters. Several of the forms appear to be 

 rmdescribed. One of the Astartes closely resembled A. seini- 

 sulcata in sculpture, but was a more tumid and orbicular shell ; 

 the other not unlike A. sulcata, is, nevertheless, different from 

 any recent or fossil species known to me ; but in so difficult a 

 group as this it is inadvisable to name species without a more 

 generous supply of material. 



The Chrysodomus seems without doubt to be identical with 

 a species recently described by Pilsbry from specimens washed 

 up on the coast of New Jersey from a submarine bed which 

 also affords Chrysodomus Stirtvpsoni Morch., _Buccinum unda- 

 tum L., and unusually large specimens of Urosal/pinx cinereus 

 Say. The New Jersey fossils have been cast up, after severe 

 storms, at Cape May, Sea Isle City and Point Pleasant, in 

 1891-2. The two following species are sufficiently well repre- 

 sented to permit of description without imprudence; the 

 Macoma is the most abundant fossil found at Gay Head. 



Nucula Shaleri, n. s. 



Shell ovate-trigonal, rather solid, moderately convex, with 

 the anterior slope very short ; internal margin distinctly and 

 rather coarsely crenulated; anterior hinge margin with eight 

 or nine > shaped teeth, posterior with about sixteen, which 

 are less angular ; muscular impressions small and the posterior 

 somewhat impressed : escutcheon narrow, not deep, rather 

 small ; outer surface sculptured with numerous, rather irregular, 

 coarse concentric ridges often discontinuous or bifurcating 

 toward the ends of the shell, the umbonal slope of each ridge 

 tending to be longer than the other ; these are crossed by fine, 

 sharp, interrupted grooves radiating from the beaks to the 

 margin. Lon. of shell, 15 ; alt., 11 ; diameter, 7 mm . 



This shell belongs to the group of i\ r . decussata and antiquata 

 Sby., which, with the exception of the small deep water south- 

 ern N . crenulata Hinds, is hardly represented on our coast 

 either recent or fossil. The typical specimens were collected 

 by Professor Shaler at Chilmark in a ferruginous gravelly con- 

 glomerate. 



Macoma Lyelli, n. s. 



Shell short, high, rounded, rather tumid, with the posterior 

 extremity strongly dextrally flexuous ; anterior slope semicir- 

 cular, passing evenly into the base ; posterior slope longer, 



