48 Forty-fifth Report on the 



The shells which are most numerous belong to the genus Val- 

 vata. Two forms belonging to the genus are found to be about 

 equally abundant. One of these is Valvata tricarinata, Say., 

 and the other is either Valvata sincera, Say., or the variety 

 simplex of V. tricarinata. In my opinion it is V. sincera. V. 

 tricarinata is said to be a very variable species, varying from 

 the typical tricarinate form through bicarinate, unicarinate and 

 ecarinate forms. The latter has been designated as variety sim- 

 plex. None of the specimens of Valvata found in the marl bed 

 under consideration showed any of the intergradations between 

 the tricarinate and ecarinate forms. All were either decidedly 

 tricarnate or decidedly ecarinate. The absence of intermediate 

 forms leads to the opinion that the ecarinate form is Valvata 

 sincera. 



A striking feature of the deposit is the absence of large 

 bivalves. The plentiful supply of carbonate of lime and the 

 luxuriant growth of mosses and other aquatic plants made the 

 locality an extremely favorable one for freshwater mollusca. 

 The presence of the remains of myriads of specimens attests the 

 truth of the above, and yet no specimens of Unio, Anodonta or 

 Margaritana were found. At the present day fifteen species of 

 these animals are abundant in ponds and streams in the immedi- 

 ate neighborhood of the marl. Mather (Geol. N. Y. p. 11) says 

 " Unios and Anodontae are sometimes found in it (marl). Piles 

 are sometimes seen on the edges of marl banks and on shores, 

 that have been carried there by muskrats, to devour the tes- 

 taceous animals." There are no Uniones in the State Museum's 

 collection of shells from marl; the largest bivalve being Sphcer- 

 ium simile, from a deposit at Little Lakes, Herkimer county, 

 SLY. 



In the muck many species of land shells were observed. A 

 list of these is not given, as it is believed that a careful search 

 would bring to light almost all the species known to inhabit the 

 neighborhood. All that were found were either on the surface, 

 or but a few inches underneath. Their presence beneath the 

 surface is due to the fact that they have been turned under by 

 the plough. 



In the collection of the State Museum are nine teeth of a fossil 

 horse which were found in 1889 by Mr. Bronk Yan Slyke, 



