226 



form in the various drainage systems ; but little attention is paid to mat- 

 ters of synonymy, for these have been elsewhere treated. The main facts 

 in geographic distribution are presented in compact form and then further 

 illustrated by a map of distribution in which the extreme limits of range 

 are shown. 



The hypsometric facts are separately presented ; the altitudes of various 

 of the forms are given on the authority of the " Dictionary of Elevations" 

 published by the U. S. G. S. The several ranges are compared and the 

 facts are then generalized for the species of each group. Attention is 

 called to the extremely limited range, both geographically and hypsomet- 

 rically, of the genus Tulotoma. 



This paper may be found in full in the American Journal of Science for 

 August, 1894. 



On .some South American characinid.e. By A. B. Ui.rey. 

 [Abstract.] 

 A study of the Characinid* collected by Charles Frederic Hart in Brazil 

 shows that he found 47 species, seven of which are new. Four of the new 

 species belong to the genus Tetragonopterus, one to Mylednus and two to 

 Apliyocarax. Descriptions of the new species will be published in the 

 annals of the New York Academy of Science, together with notes on the 

 specimens examined and analyses of the species of Cheirodon, Aphyocaraa:, 

 and TetragonojHenis. 



The effect of environment on the mass of local specie.s. By Carl H. 



ElGENMANN. 



Nearly every family of fishes represented on the Pacific slope of North 

 America has one or more of its representatives modified in a certain di- 

 rection as compared with its Atlantic slope relatives. The modification 

 consists in the increase of the number of rays of one or more of the fins 

 or in the modification of some of the rays into spines. 



In most families the difi'erences between the Atlantic and the Pacific 

 slope representatives are just perceptible, and, were it not for the concen- 

 sus of difterences in all groups would stand for nothing. 



