155 



Proceedings of the Entomological Society of Philadelphia. March and 

 April, 1862. 8vo. Pamph. 



Proceedings of the Academy of Natural Sciences of Philadelphia. Nos. 1, 

 2, 3, 4. Jan. to April, 1862. 8vo. Pamph. By Exchange. 



Quarterly Journal of the Geological Society. Nos. 6T, 68, 69, 70, for Aug. 

 and Nov. 1861, and Feb. and May, 1862. 



Bydragen tot de Dierkunde. Long 4to. 7 Aflevering. 1848-54. 



Contributions to the Natural History of the United States of America. By 

 Louis Agassiz. Vol. iv. 4to. Boston, 1862. 



Annals and Magazine of Natural History. Nos. 50, 51, 52, 53, for February, 

 March, April, and May, 1862. From the Courtis Fund. 



New England Historical and Genealogical Kegister. Vol. xvi. No. 2, for 

 April, 1862. 



Life and Letters of Washington L-ving. By his nephew, P. M. Irving. Vol. i. 

 8vo. New York, 1862. Dejjosited by the Republican Institution. 



September 3, 1862. 

 The President in the chair. 



Dr. Jackson offered some remarks upon a new method of 

 security against counterfeits in paper currency through the 

 introduction of determinate sjJecies of Diatomacese into the 

 material of the paper, or into some of the ingredients used 

 in the preparation of the stamps ; the method is the inven- 

 tion of Mr. D. J. Browne. 



Mr. E. D. Cope, of Philadelphia, was elected Correspond- 

 ing Member. 



September 17, 1862. 



The President in the chair. 



Prof. J. Wyman stated that through the kindness of Prof. Agassiz, 

 he had had an opportunity of studying the larvae of Dactylethra ca- 

 pensis from South Africa. These larv« are all considerably advanced 

 in development, are from three to four inches in length, and have the 

 hinder limbs more or less formed. The rudimentary fore limbs were 

 protruded in all the specimens but one. In several respects they 

 diiFer greatly from the larvae of other Batrachians. The head is 

 more flattened, the body is less rounded and longer, and the tail 



