GREAT LAKES COREGONIBS 



435 



prises 24 per cent of the body length. At the occiput the dorsal profile rises in a 

 smooth curve over half the distance to the dorsal and continues to the dorsal with 

 only a slight upward trend. From the dorsal the contour slopes gently to the caudal 

 peduncle. The ventral profile from the tip of the mandible to the ventral fins runs 

 like the opposite dorsal contour, curving strongly downward and backward for two- 

 thirds its extent and extending to the ventrals over its remaining one-third in a line 

 nearly parallel to the lateral line. From the ventrals to the anal the contour con- 

 verges distinctly toward the lateral line. The head is rather elongated and is con- 

 tained 4 [(3.7) 3.8-4.1 (4.3)] 92 times in the total length. 



Its dorsal profile runs in a faint but distinct convex curve to a point above the 

 center of the orbit and from thence to the occiput is often more or less concave in its 

 course. The premaxillaries are directed forward and make an angle of about 50° 

 with the horizontal axis of the head. The snout is always longer than the large eye, 

 which is contained 3.9 [(3.6) 3.8-4.2 (4.3)] times in the head. The maxillary is pig- 

 mented and extends beyond the anterior edge of the pupil but never to its center. 

 The mandible is rather frail and usually projects beyond the upper jaw. Seldom is 

 it shorter. The gill rakers on the first branchial arch are relatively short; they number 

 15 + 25 [(11) 13-15 (17) + (21) 23-26 (27) = (34) 36-41 (45)]. 93 The scales in the lateral 

 line number 85 [(71) 77-87 (91)]; 82 per cent of all the specimens examined have 79 

 or more scales. Rows of scales around the body just in front of the dorsal and ventrals 

 number 46 [(39) 41-44 (46)]; 94 just in front of the adipose and anus 37 [(32) 33-35 

 (37)]; 94 around the caudal peduncle at its commencement 26 [(23) 24-25 (26)]. 94 

 The dorsal rays are 10 [9-10 (11)]; 95 the anal rays 11 [(9) 10-12 (16)]; 96 ventral rays 

 11 [11-12]; 94 pectoral rays 15 [(15) 16-17 (18)]. 94 The dorsal margin of the pectoral 

 is usually straight. The pectorals are contained in the distance from their insertion 

 to that of the ventrals 1.6 [(1.1) 1.4-1.7 (2.1)] times. The ventral length divided 

 into the distance from their origin to the insertion of the anal equals 1.2 [(0.96) 1-1.3 

 (1.4)]. 



The color in fife is about like that of johannss. The underlying color is obscured 

 in the back by the dense pigmentation, which covers nearly uniformly the entire dorsal 

 surface and which also extends over the entire preorbital area, including all but about 

 the distal one-fourth of the maxillary. The dorsal surface of the head in front of the 

 nostrils, likewise the'~tip of the mandible, are often very dark. Pigment occurs, too, 

 on the sides, abundantly above but only sparsely below the lateral line. The dorsal 

 and caudal fins are rather widely margined with black, most intensely on the median 

 rays of the caudal. The dorsal margin of the pectorals often is lined with black, and 

 the membranes of the anal are frequently sparingly sprinkled with pigment. The 

 ventrals are usually immaculate. In spirits the color fades, leaving obvious the details 

 of pigmentation. 



Pearl organs are developed by at least the breeding males, as evidenced^by the 

 taking of specimens^showing incipient pearls ; but no breeding fish have been examined 

 by me. 



•a The figures in brackets, unless otherwise marked, are given for 174 examined specimens, 120 of them paratypes, which range 

 in length from 122 to 245 millimeters. 



n Two hundred and twelve specimens. 

 •< Twenty-two specimens. 

 •* One hundred and fifty-four specimens. 

 ,! One hundred and forty-four specimens. 



