. The Canadian field-naturalist. 28 The Canadian Field-Naturalist Vol. 106 al 226 mm TL, and the Royal Ontario Museum (ROM) collection includes a 232 mm male (Figure 1) collected in Alberta in 1964 (ROM 25919). The following account is largely based on descriptive material from Sigler and Miller (1963), Carl et al. (1967), Smith (1966), and Scott and Grossman (1973). The body is elongate, cylindrical and somewhat compressed caudally. The snout is broad and heavy, the eye small, the mouth large and ventral, the edge of the lower jaw having a sharp-edged cartilaginous sheath and the lower lip ha
. The Canadian field-naturalist. 28 The Canadian Field-Naturalist Vol. 106 al 226 mm TL, and the Royal Ontario Museum (ROM) collection includes a 232 mm male (Figure 1) collected in Alberta in 1964 (ROM 25919). The following account is largely based on descriptive material from Sigler and Miller (1963), Carl et al. (1967), Smith (1966), and Scott and Grossman (1973). The body is elongate, cylindrical and somewhat compressed caudally. The snout is broad and heavy, the eye small, the mouth large and ventral, the edge of the lower jaw having a sharp-edged cartilaginous sheath and the lower lip has the shape of paired wings (Figure 1). There are definite notches at the corners of the mouth (at the point of lateral connec- tion of the upper and lower lips) and an incomplete medial cleft to the lower lip, which is markedly con- vex anteriorly, with three to five rows of large, round papillae covering the base. The upper lip is large and the outer surface without papillae; there are no teeth in the mouth and the pharyngeal teeth are flat and comblike. There are generally 23 to 37 gill rakers on the external row of the first arch and 31 to 51 on the internal row. The fontanelle is usual- ly reduced to a narrow slit, but may be obliterated; the peritoneum is black or dusky; the intestine is long with six to 10 coils anterior to the liver; there are no pyloric caeca. A two-chambered swimbladder is present, but is reduced, the slender posterior chamber extending to about the point of origin of the pelvic fins. Post-weberian vertebrae number 38 to 44, usually 40 to 43. Cycloid scales cover the body, usually crowded towards the head; the lateral line is complete and straight, the number of scales varying from 60 to 108 throughout the range (79-89 in British Columbia). There is one dorsal fin with eight to 13 soft rays (over the range, 10 or 11 in ); the caudal fin is not long or deeply forked; the anal has seven rays; the pelvics are located well back in line with the middle
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Keywords: ., bookauthorottawafi, bookcentury1900, bookdecade1910, bookyear1919
