230 T. G. Brown — Fauna from Chappaquiddick Island. 



substantiate the point. " A systematic exploration of all expo- 

 sures was therefore prosecuted ; hundreds of the concretions 

 and shalj fragments were broken open and critically examined 

 and the result was a collection, not only of molluscs but also of 

 plant remains, a few of which were found sufficiently well pre- 

 served for identification."* 



Upon his return Dr. Hollick submitted the molluscs to 

 Professor R. P. Whitfield of the American Museum of Natural 

 History for a hasty examination, and concerning them Pro- 

 fessor "Whitfield spoke thus : " 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 Jf.plicatida, of the harbor here ; anAnomia 

 which might pass for A. gigantaria of the lower greensand 

 marls of New Jersey, if it were not for the Modiola • also a 

 single imperfect internal cast of a small (young?) Peciunoxdus 

 not enough of it to tell the species, and a small bivalve of 

 which I cannot 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." f 



These fossils were also submitted to Professor Grabau of 

 Columbia University for examination. " Mr. Grabau is of the 

 opinion that they may represent a new fauna, of more recent 

 age than the Cretaceous, and this is quite consistent with the 

 conditions under which they occur, so far to the south of any 

 recognized Cretaceous outcrop. The character of the matrix 

 also, with a single exception, is notably different from that in 

 which undoubted Cretaceous molluscs have been found else- 

 where, being a micaceous sandstone instead of a hardened clay 

 or greensand." % 



A careful study and detailed comparison of these fossils 

 with descriptions, figures, and specimens of the Cretacic and 

 Eocene species shows that these fossils represent a new fauna 

 of Eocene age. This fauna, however, differs widely from that 

 of the Eocene deposits of the South Atlantic coast and seems 

 to be more closely allied in general to the Eocene of England. 

 Some of the specimens are very well preserved, while others 

 are only represented by external and internal molds. Many of 

 these molds are of such a nature and so well preserved that a 

 wax impression can easily be taken and the characters of the 

 fossil observed and compared. The following descriptions and 

 comparisons include the best preserved and most typical speci- 

 mens. Some of these are not perfect enough to be described 

 as new species, but most of them can be genericaily placed. 



*Bull. New York Botanical Garden, vol. ii, No. 7, pp. 399-400. 

 f Bull. N. Y. Botanical Garden, vol! ii, No. 7, p. 400. 

 % Ibid., p. 401. 



