NATURAL SCIENCES OF PHILADELPHIA. 101 



April 1th. 

 Vice President Bridges in the Chair. 



A communication was presented for publication in the Proceedings, 

 entitled : 



Description of six new species of fresh water and land shells, by 

 Isaac Lea. Referred to a Committee. 



On leave granted, Dr. LeConte moved that a special vote of thanks 

 be tendered to Dr. Benjamin Vreeland, U, S. N., for his valuable do- 

 nation of Esquimaux Skulls received this evening. Which motion was 

 unanimously adopted. 



Ajiril I'ith. 



Vice President Bridges in the Chair. 



Mr. Lea called the attention of the Academy to the specimen of 

 Unio Spinosus presented by him this evening The inner face of the 

 valve has an arch leading toward the spine, which is probably hollow ; 

 thus confirming the view of the mode of formation of the spine pre- 

 viously stated by him. 



April 21st. 



Vice President Bridges in the Chair. 



A Communication was received from W. J. Taylor, entitled " Ex- 

 amination of a Nickel Meteorite from Oktibbeha county, Miss.," which 

 was referred to a Committee. 



April 2Sth. 



Vice President Bridges in the Chair. 



The Committees on Mr. Lea's paper, entitled " Description of six 

 new species of fresh water and land Shells," and on Mr. Taylor's " Ex- 

 amination of a Nickel Meteorite, &c.," reported in favor of publication. 



Description of Six new species of Fresh Water and Land Shells of Texas and 



Tamanlipas, from the Collection of the Smithsonian Institntion. 



BY ISAAC LEA. 



Unio Berlandierii. Testa laevi, subelliptica, inflata, postice subrotundata 

 infequilatcrali ; valvulis crassis, antice crassioribus: natibus grandibus, elevatis, 

 tumidis, ad apices minute undulata; epidermide micans, tenebroso-fuscEl, obso- 

 lete radiata ; dentibus cardinalibus magnis, erectis, subcompressis, valde crenu- 

 latis et in utroque valvule duplicibus ; lateralibus longis, crassis, subcurvis 

 lamellatisque ; margarita vel purpurascente vel salmonis colore tincta et irides- 

 cente. 



Hab. Matamoras, Tamaulipas, Mexico. Luis Berlandier, M. D.* 



* The collection made by Dr. Berlandier was purchased by Lieut. D, N. Couch, 

 U. S. A., and liberally presented to the Smithsonian Institution. 



1857.] 8 



