58 Emerson — Bivalve from the Connecticut River Trias. 



The bowlder id front was not quite in focus but a dim line 

 runs across the middle of the front from the upper left hand 

 corner to the lower right hand corner and the portion below 

 that line is distinctly striated, while the part above that line is 

 weathered several millimeters deep by long exposure to the 

 weather as it projected on the cliff while the lower portion was 

 protected within the solid mass of the rock. Dr. Netting 

 explained to me the conditions of the occurrence and there can 

 be no doubt about the glacial character and the Carboniferous 

 age of the deposit. I send this short article because doubt has 

 been expressed in a recent standard text-book as to the reality 

 of the Carboniferous Glacial period. 



Art. YIII. — A new Bivalve from the Connecticut River 

 Trias ; by B. K. Emerson. 



A few days ago my former assistant, Mr. Chas. S. Merrick, 

 of Wilbraham sent me a large slab of sandstone of a buff color, 

 much stained by malachite, containing several indistinct casts 

 of a unio-like bivalve. 



The shell seems to be one of those fresh or brackish water 

 forms common in the Trias allied to the Unionidee. It may be 

 compared with the Anoplophora lettica Quenstedt,* and may 

 be called Anojflojphora Wilbrahamensis. It is a distinctly unio- 



shaped shell 38 rara long, 18 ram ' high, 

 7 mm thick. The exterior is smooth 

 with fine lines of growth. The 

 mantel impression is quite. deep as 

 preserved on the central portion of 

 the length. The beak rises very 

 slightly and the hinge line is long 

 and straight and there is in the fig- 

 ure what seems to be the impression of a long, posterior tooth, 

 and above this a slight groove at the place of attachment of the 

 ligament. 



The large slab contains 14 imperfect casts, all of which may 

 well belong to one species. 



I do not know of any other bivalve shell from the Trias in 

 Massachusetts. 



*Pal., plate lxiii, fig. 2S. 



