HEAD:
Summary: Head large, but varying much in size, fitting 3½ to 4½ times into body
length, narrowed anteriorly. Interorbital space 15 to 22% of head length. Mouth moderately
large, terminal; lower jaw shorter than upper. Chin with well developed barbel. Eye moderately large,
about ½ length of snout. Gill openings very wide, extending upward to at least the level of the
pectoral fins. Gills four in number, with a slit behind the fourth; no pseudobranchiae present. Edge of
preopercle usually covered by skin. Lateral line pores present on head.
Literature: Jordan and Evermann 1898:
Reference to family Gadidae: Page 2531(text) - "...mouth large, terminal; chin with a
barbel, more or less developed. Gill openings very wide. Gill membranes separated or somewhat
united, commonly free from the isthmus..." "Gills 4, a slit behind the fourth. No pseudobranchiae.
Edge of preopercle usually covered by skin of head." References to genus Gadus:
Page 2532 (key) - "Lower jaw included; barbel well developed..."
Page 2540 (text) - "Head narrowed anteriorly; mouth moderate..." "...chin with a barbel..."
Reference to Gadus morhua (as Gadus callarias) and Gadus macrocephalus:
Page 2540 (key) - "Eye moderate, about ½ snout in adult..." Reference to Gadus morhua:
Page 2541 (text) - "Head 3½ to 4½..." "Head large, but varying much in size..." "Eye
moderate, about ½ length of snout." Robins and Ray 1986:
Reference to family Gadidae: Page 92 (text) - "Many have barbels on the snout and chin." Reference to Gadus morhua -
Page 93 (text) - "Lower jaw shorter than upper jaw. Barbel well developed." Plate 15 (caption) - "Lower jaw shortest;
chin barbel long." Cohen et al. 1990:
Reference to family Gadidae: Pages 13 (key) - "Gill openings extending upward to at least the level of the pectoral fins."
Page 18 (text) - "Gill openings extend upward above the level of the pectoral fins."
References to genus Gadus: Page 21 (key) - "Eye smaller, less than snout length. Mouth generally
horizontal to moderately oblique." Page 22 (key) - "Lateral line pores present on head." "Upper jaw longer than lower." Page 41 (text) - "Lower jaw shorter than upper..." "Chin barbel well developed."
"...lateral line pores present on head." Reference to Gadus morhua:
Page 41 (key) - "Head relatively narrow, interorbital space 15 to 22% of head length." Page 45 (text) - "Head relatively
narrow, interorbital space 15 to 22% of head length."