2794 Bulletin //, United States National Museum. 



the middle rays but little longer than the others ; anal small, somewhat 

 pointed; margin of dorsal somewhat concave; caudal lunate, not deeply 

 forked. Muciferous canals on head not strongly developed. Scales mod- 

 erately large; lateral line nearly straight, not running upward toward 

 nape. This species differs from C. occidentalis, to which it is related, in 

 the smaller head, longer, more pointed snout, smaller eye, larger scales, 

 and its much smaller fins. In C. occidentalis the pectoral fins are falcate, 

 while in this species they are more rounded; the veutrals also are less 

 pointed. Length a foot or less. Coastal streams of middle western Ore- 

 gon; known from Tsiltcoos Lake and the Siuslaw River, (tsiltcoosensis, 

 from the type locality.) 



Catostomus tsiltcoosensis, EVEKMANN & MEEK, Bull. U. S. Fish Comm. 1897 (Jan. 6, 1898), 

 68, fig. 1, Tsiltcoos Lake, Lane County, Oregon. (Type, No. 48479. Coll. Dr. Seth 

 E. Meek.) 



Page 180. The species called Catostomus fecundus in the text belongs 

 in the genus Chasmistes, to which it should be transferred as Chasmistes 

 fecundus (Cope & Yarrow). 



Page 182. The species of Chasmistes are not confined to the Great 

 Basin. One species (C. brevirostris) occurs in the Klamath Lakes basin. 



Page 183. The species called Chasmistes luxatus in the text belongs to 

 a genus distinct from Chasmistes, .which may be characterized as follows : 



93(a). DELTISTES, Seale. 

 Deltistes, SEALE, Proc. Gal. Ac. Sci., ser. 2, vol. VI, 1896, 269 (luxatus). 



This genius is close to Chasmistes, agreeing with it in every respect 

 except in the peculiar structure of the gill rakers. In Chasmistes they are 

 as in Catostomus, while in Deltistes they are broad, shaped like the Greek 

 letter A (delta), and their edges are unarmed and entire. Lower pharyn- 

 geals weak, with numerous small teeth. Deltistes luxatus (Cope) is the 

 single known species. (SeXra, the Greek letter corresponding to D.) 



After Chasmistes cujus add : 



297 (a). CHASMISTES STOMIAS, Gilbert. 



Head4i; depth 4; eye 7; snout 2$; maxillary (measured from free end 

 to tip of snout) 3Jr ; mandible 2|. D. II, 11 ; A. I, 7 ; scales 13-85-10 ; inter- 

 orbital width 2f; vertical depth of head at mandibular articulation 2^. 

 Head small, body heavy forward, the back strongly and regularly .arched 

 from snout to origin of dorsal fin, thence declined in a nearly straight 

 line to base of caudal; ventral surface nearly straight. Premaxillary 

 spines strongly protruding, forming a prominently projecting snout; 

 mouth rather small, inclined upward at an angle of about 40, maxillary 

 scarcely reaching vertical from front of anterior nostril; width of mouth 

 If in snout or 4f in head; upper lip thin, without papilke; lower lip thin, 

 interrupted at symphysis, forming narrow lateral lobes, the width of which 

 is about 2| times in their length ; faint indications of a few papillae ; 

 mucous canals forming ridges, the pores conspicuous; gill rakers long, 



