404 PROCEEDINGS OF THE ACADEMY OF [1888. 



To the Proceedings of the Academy of Natural Sciences, and to 

 the American Journal of Conchology Mr. Tryon contributed sixty- 

 four papers, between 1861 and 1873, inclusive, a list of which is ap- 

 pended. 



In conjunction with Mr. Wm. G. Binney,in 1864, Mr. Tryon edited 

 the complete writings of C. S. Rafinesque on recent and fossil conch- 

 ology. In 1866, he published A Monograph on the terrestrial mol- 

 lusca of the United States; in 1870, A Monograph of the Fresh- 

 water univalve mollusca of the United States ; in 1873, American 

 Marine Conchology, and A Monograph on the Streptomatidse (Amer- 

 ican Melanians) of North America. This work was prepared at the 

 instance of the Smithsonian Institution, and published in its Miscel- 

 laneous Collections, in December. It was a result of several years' 

 study. The manuscript was completed in 1865, and laid aside. At 

 the end of seven or eight years, he again took up the subject, which 

 he regarded as " one of the most interesting and difficult branches of 

 American Conchology," and found himself " inclined to question 

 many of the conclusions " which he had reached. In the preface of 

 the work he says: — "A more enlarged acquaintance with fresh- 

 water shells convinces me that a much greater reduction of the 

 number of species than I have attempted must eventually be made; 

 but until the ])rolific waters of the Southern States liave been sys- 

 tematically explored, and a great collection of specimens obtained, 

 which shall represent every portion of those streams and include as 

 many transitional forms as can be procured, a definite monograph 

 of our Melanians cannot be written." 



More conclusive evidence of Mr. Tryon's habitual devotion 

 to accuracy in all his work than is contained in thfe history of the 

 j)reparation of this monograph is not required. 



Mr. Tryon, for the sake of relaxation, left Philadelphia, May 

 1874, and returned September 19. During an absence of four 

 months, he visited England, Holland, Belgium, Germany, France, 

 Switzerland, Italy. 



In a series of letters he wrote good-humored, cheerful sketches of 

 his impressions of people and places at which he halted on his way. 

 They were published in the Amateur; a monthly magazine of Music 

 and Literature. 



He visited England and the continent of Europe again in 1877. 

 His route included Liverpool, London, Paris, Marseilles, and thence 

 along the coast of the Mediterranean to Nice, San Remo, Genoa, 



