174 CONTRIBUTIONS TO NORTH AMERICAN ICHTHYOLOGY III. 



body. It is said to be very abuudant in Lake Talioe. " They are caught 

 in nets and sometimes with the hook, but like all this family are rather 

 poor as food" {Cooper). Acomus gcnerosus of Girard, with which this 

 species has been identified, is a very different species, belonging to a 

 different genus. 



Specimens in United Stales NattoiMl Musenni. 



Number. Locality. 



Collector. 



5240 Lake Tahoe (types C. fahoensis) 

 17109 Lake Tahoe 



J. G. Cooper. 

 H. W. Heushaw. 



33. CATOSTOMUS ROSTRATUS {Tilesius) Jordan. 

 Siberian Sucker. 

 1813 — " Cyprinus rostratus Tilesius, M6m. Ac. Sc. St. Pdtersbourg, iv, p. 454, tab. 15, 

 figs. 1-2, 1813." 

 Cyprinus rostratus Pallas, Zoogr. Rosso- Asiat. iil, 308. 



Cyprius rostratus GIJnther, Cat. Fishes Brit. Mus. xii, 12, 1868. (As doubtful 

 species of Catostomus.) 

 1844 — Catostomus tilesii Cuvikr &. Valenciennes, Hist. Nat. des Poissons, xvii, 469, 

 1844. 



Habitat. — Eastern Siberia. 



No writer since Tilesius seems to have observed this fish- It is, how- 

 ever, unquestionably a species of (Jatostomus, allied to and perha[)s even 

 identical with G. longirostris. The following is Tilesius's description 

 of this species, as quoted by Pallas: — 



" Descriptio Cyprini rostraii Tungusis ad Covyraain fluv-.Tschukulschan et Jucagins 

 Onatscha dicti. Tab. XV, Fig. 1-5. {Der RiLffeJkarpfen, Rampkopf.) 



" Maynitudo in adultis pedem superat, sed trium spithamaruru longitudinem vix 

 attingit. Caput osseura longnm antico rostro descendente truncatum e quino simile 

 quain ob rem Ruthcnis. 



" iLO(f& dicitur aliis Produst, quoniam os subtus, ut In (sic) Cotto cataphracto vel 

 Agono accipenserino, sed rictus oris vel oriflcium lunatum non amplum sed augustum 

 labiis crassis pinguibus marginatum, labium anterius foruicatum, ambitusemicircuhire 

 ossibus labial ibus vel mystaceis ad fneuum oris descendentibus arcuatis lateraliter 

 lectum, labium posterius minus, rectum, ab anteriori iuclusum amplexum papillis 

 numerosissimis granulatum. 



" Oculi lateralis a rostro remoli operculo posteriori branchiali approximati ovales, 

 iridibus anrcis superne angustioribus, pupilla supra centrum posita. Hares ad mar- 

 ginem orbita> antcriorem dnplices iu sulco profundo osseo. Opercalo hranchiaVm tri- 

 lamellata, lamella anterior cum ossibus maxilljB superioris conjuiicta ellyptica angusta 

 ad orbii'a) uiarginem auteriorom ascendens inferius laraellaB sccundcc tenerrimse 

 angustiori orbitam in£eriorem formauti imposita, lamina ossea subjacens, operculum 



