M. E. Dodge — Pleistocene Fossils from Mass. 101 



cliff at Winthrop : Lunatia groenlandica Stimpson, Scapharca 

 transversa Adams, Buccinum undatum Linne, Ilyanassa 

 obsoleta Stimpson. Of the above, all but the last are undoubt- 

 edly new discoveries. The last has however been noted by 

 Yerrill* as coming from this locality, having been discovered 

 by Dr. Stimpson. I have examined all the references I could 

 find to discover where Dr. Stimpson has announced the find- 

 ing of the species, but without success. Even in the article,f 

 in which he changes the generic name from Nassa to Ilyanassa, 

 he makes no mention of its occurring as a fossil either in this 

 locality, or anywhere along the shore of Massachusetts Bay. 



I have also found a small fragment of shell, the species of 

 which I have thus far been unable to have determined. Prof. 

 Yerrill, to whom the specimen was referred for identification, 

 states in a letter, "I have compared it with all similar living 

 shells of our Eastern Coast fauna and find nothing just like it 

 in sculpture. It probably belongs to the Veneridce or Luci- 

 nidce, but there is too little of it to be sure even of the family. 

 It may be Tertiary or even Cretaceous, for I have had speci- 

 mens of soft limestone bowlders from the drift of Cape Cod 

 containing well preserved Cretaceous shells." Mr. J. B. 

 Woodworth has shown me some specimens which he has col- 

 lected from the Miocene of Stpiibnocket, Martha's Vineyard, 

 which this fragment resembles in a marked degree. If this 

 species should prove to be not now known on the Atlantic 

 seaboard, it would be the first instance, as far as I know, of a 

 species found as a fossil in the Glacial drift but not now living. 

 Mr. Upham says 4 " All these species which remain from the 

 marine fauna that existed before the formation of the last ice 

 sheet, are found living at the present time in the adjoining 

 waters of Massachusetts Bay." Venus mercenaria however is 

 more truly a southern form and is only found scatteringly in 

 the Bay. It is thus very similar in its distribution to Scapharca 

 transversa, which is not found north of Cape Cod. Finding 

 thus this species as a fossil in Massachusetts Bay, which now 

 lives only in the warmer waters south of Cape Cod, we have a 

 strong bit of additional evidence to help prove that the waters 

 of Massachusetts Bay, just previous to the advent of the last 

 ice sheet, were somewhat warmer than at present, an hypothe- 

 sis which is now pretty generally conceded to be true. 



Recent discoveries of Post-glacial fossils from dredgings in 

 Boston Harbor, noted by Mr. Upham,§ show us conclusively 



* Report upon the Invertebrate Animals of Vineyard Sound, U. S. Fish Com- 

 mission Report, 1871-72. 



f Am. J. Conchol., vol. i. p. 61. 

 ■ % Proc. Bost. Soc. Nat. Hist., vol. xxiv, p. 134. 



| Proc. Bost. Soc. Nat Hist., vol. xxv, pp. 305-316. 



