112 CONTEIBUTIONS TO NOETH AMERICAN ICHTHYOLOGY IV. 



a. Basal brancMhyals 2; pharyngeal teeth numerous, pectinate; maxillaries 



forming part of the margin of the upper jaw CATOSTOMiDiE, 30. 



aa. Basal branchihyals 3 ; pharyngeal teeth few ; margin of upper jaw formed by 



premasillaries alone Cyprinid^, 31. 



** Brain case not produced between orbits ; basis cranii double, sometimes with mus- 

 cular canal ; 4 to 1 superior pharyngeal bones ; lower pharyngeals not falci- 

 form; 3 basal branchihyals; teeth iu j aws of ten present. (Charadni.) 



Characinid/E, 32. 



Family XXX.— CATOSTOMID^. 



{The Suckers.) 



Body oblong or elongate, usually more or less compressed. Head 

 more or less conoid. Opercles normally developed. Nostrils double. 

 No barbels. Mouth large or small, usually protractile and with fleshy 

 lips. Margin of ui^per jaw formed in the middle by the small premax- 

 illaries, and on the side by the maxillaries. Jaws toothless. Lower 

 pharyngeal bones falciform, armed with a row of numerous comb-like 

 teeth. Branchiostegals 3. Gill membranes more or less united to the 

 isthmus, restricting the gill-openings to the sides. Gills 4, a slit be- 

 hind the fourth. Pseudobrancbite present. Scales cycloid, large or 

 small. Lateral line decurved, sometimes wanting. Head naked. Fins 

 not scaly. Dorsal fin comparatively long (of 11-50 rays), without true 

 spine. Anal fin short. Caudal fin more or less forked. Ventrals ab- 

 dominal, with about 10 rays. Pectoral fins placed low, without spine. 

 No adipose fin. Belly not serrated. Alimentary canal long. Stomach 

 simple. No pyloric coeca. Air-bladder large, divided into two or three 

 parts by transverse constrictions, not surrounded by a bony capsnle. 

 Genera 14 or fewer; species about 60 ; inhabiting the fresh waters of 

 North America, two species in Eastern Asia. They are not much valued 

 as food fishes, the flesh being flavorless and full of small bones. 



(Cyprinidw, group Catostomina Giinther, vii, 12-24.) 



* Dorsal fin elongate, its develojied rays 25-50 iu number ; air-bladder in two parts, 

 t Fontanelle present ; body ovate ; scales large, {Bubalichthyince.) 

 a. Dorsal rays 24-33. 



&. Mouth large, terminal, protractile forwards; lips thin ; j)haryugeal bones and 



teeth weak Ictiobus, 59. 



bh. Mouth smaller, inferior, protractile downwards, 

 c. Pharyngeal bones strong, the te^th comparatively coarse and large, in- 

 creasing iu size downwards Bubalichtiiys, 60'. 



cc. Pharyngeal bones narrow, with the teeth thin and weak . . Carpiodes, G1. 

 tf Fontanelle obliterated by the union of the parietal bones ; body elongate. (Cyclep- 

 tince.) 

 d. Mouth small, inferior, with thick papillose lips ; scales rather small. 



Cycleptus, 62. 



