150 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY — III. 



Fius moderate, the dorsal rays about 12, tbe anal 7 : pectorals 

 rather long, not (iiiite reachiug veutrals: veiitrals reaehiug veut : anal 

 tin hiii:h, reaching caudal : caudal fin rather long, its lobes equal. 



Scales moderate, large ou the caudal peduncle, much smaller and 

 crowded auteriorly, CO to G5 in the lateral line, about 18 iu a transverse 

 series iVom dorsal to ventrals. 



Sexual peculiarities unknown. 



Coloration usual. 



Air-bladder in two parts. 



Size moderate or rather large. 



The single species now included iu this genus is known only from 

 Utah Lake. Its describers referred it to the genus Catostomus, but 

 made no mention of its singular mouth and lips. The original type of 

 the species is in very bad condition, the mouth being shrunken and dis- 

 torted, and the bones of the head protruding through the skin, so that 

 the peculiarities of the species are hardly recognizable.* 



Gcmric Characlerizationa. 

 Chasjiistes Jordan, 1873. — " This genus is distiuguisbed from Catontomim by the 

 very large, terminal mouth, tho lower jaw being very strong, oblique, its length about 

 one-third that of the head. The lips are little developed, and are very nearlj' smooth. 

 The type of the genus is C. fecundua Cope & Yarrow." — (Jordan, Bull. U. S. Geol. Sun: 

 Terr. vol. iv, No. 2, p. 417, 1878.) 



ANALYSIS OF SPECIES OF CHASMISTES. 



* Dejith about .^ in length; head 3 j ; interorbital space broad, 2i in head; eye to 7 

 in head ; width of the open mouth '.^ in head. Dorsal 12. Anal 7. Scales 

 9-G3-8. Color dusky above, pale below ; tho scales of the back and sides pro- 

 fusely covered with dark punctulatious fecindus, 23. 



L'3. CnASMISTES FECUNDUS {Cope d- Yarroic) Jordan. 

 Sucker of Utah Lake. 

 187G—Ca(oiiiomu8 fecundua CorK & YaI!i:uW, Wheeki's Expl. \V. l(i(i;li Mer. v, Zool. 

 G78, pl.xxxii, f. 1, 1 a. 

 Calo8tomuHfccnndusJonr>AS & Copelani>, Check List, W], 1>1G. 

 ChaamiatcaftcnnduxJoi.v.Mi, lUill. Ilayden's Geol. Surv. Terr. vol. iv. No. 2, 117, 

 1878. 

 IL\BIT.VT. — Utah Lake, Utah, where it is excessively abundant. Not yet noticed 

 elsewhere. 



This singular species has been overlooked until quite lati'ly. ])r. 

 Yarrow states that it " is abundant iu Utah Lake, and is called Sucker 



•In fact, this specimen in its jiresent condition looks to me more Wko Calostomuaocci- 

 dinialis, but the tigiiro iiublislir<l by Cope & Yarrow represents C. J'lcundua. IJolh 

 S[)ccie8 occur in Utah Lake. 



