48 



November 17, 1841. 

 The President in the Chair. 



On motion of Dr. Gould it was voted that the Report of 

 the Committee on M. Vattemare's plan be transmitted to 

 Dr. Walter Charming by the Corresponding Secretary. 



Mr. Couthouy presented to the Society a very large speci- 

 men of Mactra giga?itea, and stated that he has received 

 from Chelsea three living specimens of My a truncate, the 

 first ever obtained directly on our coast. They differ some- 

 what from those found on George's Bank. 



Mr. Couthouy also made some remarks on certain errors, into 

 which he believed Professor Lyell had fallen in regard to the for- 

 mation of the Coral Islands in the Pacific, and announced his in- 

 tention of preparing a paper on that subject for the Journal. 



Dr. Gould read a paper entitled "Descriptions of twenty- 

 five new species of New England Shells," by J. W. Mighels, 

 M. D., and Prof. C. B. Adams, of which the following are 

 regarded as new. 



Thracia truncata, Migh. T. testa parva, solida, per-inequilate- 

 rali, postice truncata, et striata : callo nymphali producto, haud 

 cochleariformi. Length, .75 inch ; height, .5 inch. Habitat, Cas- 

 co Bay, Me. 



Cyclas minor, Adams. C. testa minima, ovata, inequilaterali ; 

 natibus tumidis, approximatis ; marginibus rotundatis ; dentibus om- 

 nibus fortibus. Length, .18 inch ; height, .15 inch; width, .11 

 inch. Habitat, Wey bridge, Vt. 



Cyclas nitida, Migh. C. testa sub-ovat.a, inequilaterali ; natibus 

 parvis, haud approximatis ; dentibus lateralibus fortibus, cardinali- 

 bus obsoletis. Length, .3 inch. ; height, .24 inch ; width, .2 inch. 

 Habitat, Norway, Oxford Co., Me. 



Nucula delphinodonta, Migh. N. testa parva, solida, trigona, 

 transverse sub-sulcata ; angulis umbonalibus duobus ; natibus pro- 

 minentibus, sub-terminalibus ; dentibus anticis tribus, posticis sep- 

 tem, elevatis, conicis, acutis. Length, .13 inch ; height, .11 inch ; 

 width, .09 inch. Habitat, Casco Bay. 



Nucula Cascoensis, Migh. N. testa ovato-lanceolata, sub-inequi- 



