NATURAL SCIENCES OF PHILADELPHIA. 151 



Prof. Emmons exhibited a drawing of a fossil head, supposed to be- 

 long to Clepsysaurus, found in Chatham Co., North Carolina: it was 

 covered with plates, some of which were exhibited, and had a very 

 elongated slender snout, expanded at the tip, with the nostrils situated 

 at the base. 



May 2iik. 

 Mr. Lea, President, in the Chair. 



Seventy-seven members present. 



A paper was presented for publication in the Proceedings, entitled 

 Ichthyological Notices by Charles Girard, M. D. 



And one for publication in the Journal, entitled New Unionidas of 

 the United States, by Isaac Lea. 



Which were referred to Committees. 



The death, at Berlin, of Baron Alexander von Humboldt, late a Cor- 

 respondent of the Academy, was announced. 



May olst. 

 Viee-President Bridges in the Chair. 



Fifty-one members present. 



The Report of Proceedings of the Biological Department for the 

 present month was read. 



On report of committees of the Biological Department, the papers 

 entitled, The Pathological Relations of Cancer, by J. H. Packard, M.D., 

 and On two new varieties of Wourari, Carroval and Vao, by William 

 A. Hammond, M. D., and S. Weir Mitchell, M. D., were recommended 

 for publication in a medical journal. 



On report of the respective Committees, the paper entitled, New 

 Unionidae, of the'United States, by Isaac Lea, was ordered to be publish- 

 ed in the Journal. 



And the following in the Proceedings : 



Descriptions of Twenty-one New Species of Exotic TJNIQNIDiE. 



BY ISAAC LEA. 



Unio sikkimensis. Testa, lasvi, obovata, insquilaterali, subinflata, postice 

 obtuse biangulata ; valvulis crassiusculis ; natibus prominulis ; epiderinide 

 luteo-fusca, eradiata ; dentibus cardinalibus parvulis, brevibus crenulatis. 

 in utroque valvulo duplicibus; lateralibus brevibus subcurvisque ; margarit;! 

 alba et iridescente. 



Hab. Sikkim, India. H. Cuming and Prof. Hanley. 



Unio dimindtis. Testa plicata, corrugata, subsulcata, elliptica, insquilaterali, 

 eonipressa, postice obtuse angulata ; valvulis crassiusculis; natibus subpromi- 

 nentibus, aJ apices undulatis acuminatisque; epidermide lutea eradiatiique ; 

 dentibus cardinalibus parviusculis, compressis, erectis, crenulatis, in utroque 

 valvulo duplicibus ; lateralibus subbrevibus rectisque ; rnargarita, pallido-sal- 

 ynonia et iridescente. 



Hab. East Africa. H. Cuming and Prof. Hanley. 



1359.] 



