ADDENDA. 355 



On page 188, after M. palustris, add: 



2. (b) R, circulosa. Rice and Davis {sp. nov). Hoos- 

 IBB Feog. Head broad; body, head and sides with the 

 ground color largely predominating, and with narrow 

 rings of a greenish slate color, which become larger and 

 more irregular posteriorly; hind legs black, crosseji with 

 irregular lines of yellowish slate color; fore limbs simi- 

 larly marm orate; tympanum black with pale ring; below 

 chiefly yellowish white; toes very long; size medium: 

 L. 3|-. Benton Co., Indiana, lately discovered by Mr. 

 E. F. Shipman. (Abridged from Mr. Rice's Notes.) 



On page 271: 



Genus S/ILMO. 



Since the part of this work referring to the Salmonidce 

 has been stereotyped. Professor Gill and the writer have 

 been enabled to review the various species of that family 

 found in the United States. Under the genus " JSalmo" 

 as defined in the text, at least four very distinct genera 

 are confounded, which may be briefly diagnosed as 

 follows: 



* Anal fin elongate, of 14 to 17 rays, vomer narrow, long, flat, 

 with weak teeth, no hyoid teeth ; snout in adult males in the 

 spawning season in typical species greatly distorted, the 

 premaxillaries prolonged, hooking over the lower jaw, 

 which in turn Is greatly prolonged upward and forward 

 and somewhat hooked at tip ; the teeth of the premaxillaries 

 and of the tip of the lower jaw being then greatly enlarged; 

 a fleshy hump also developed before the dorsal fin ; species, 

 black-spotted. Oncobhynchus, 1. 



** Anal fin short, of 9 — 13 rays. 



t Vomer flat, its toothed surface plane ; teeth on the shaft of 

 the vomer in two alternating rows or in one zigzag row, 

 placed directly on the surface of the boue, not on a free 



