FISHES FROM THE BASIN OF MACKENZIE RIVER. 
25 
can not be given. Axillary scale 22 mm. long. ^Adipose lin large, inserted vertically 
aboA^e last anal rays, its beiglit from tip to posterior end of base equaling vertical 
diameter of eye. 
D. Ill, 12 or II, 11 ; A. iii, 12 or ii, 11. Lateral line, 85 to 87 ; 11 or 12 scales in an 
oblique series downwards and forwards from front of dorsal to lateral line. Nothing 
can be made out concerning the original color of these specimens. 
Thymalliis sigiiifer Richardson. 
Three specimens of this form (Nos. 809, 810, and 811, L. S. Jr. Univ. Museum) 
are at hand from the Mackenzie Eiver near Fort Simpson. They have, unfortunateljq 
suffered much in transportation, but the following points can be verified: 
Scales in lateral line 88 or 89, not including the smaller ones on base of caudal. 
The dorsal fiu is very high, and must have been at least tAvo seveuths length of body, 
judging from one specimen in which one of the posterior rays remains nnmutilated. 
Spots on membrane of dorsal fiu numerous. Traces off rows are visible in the broken 
fin, and at least 10 rows of spots must have been present. The gill-rakers are short, 
as usual, the longest equaling diameter of pupil; 12 or 13 are resent on horizontal 
limb of lower arch. Dorsal fiu with 22 or 23 rays, including the anterior rudimentary 
rays. 
Stenodus mackeiizii Richardson. 
One specimen, 83 cm. long, from the Delta of the Mackenzie Eiver (No. 807, L. S, 
Jr. Univ. Museum). 
Head 4| in length to base of tail; maxillary reaching a vertical behind pupil, its 
length very slightly more than one-third head. Suiiplemental bone long and narrow, 
nearly as wide as the maxillary, the anterior end notched, the angle above the notch 
sharply j)ointed, the lower angle bluntly rounded. 
The teeth are all weak and flexible, bristle-like. They are present in a narroAV 
band in upper jaw, the baud extending laterally onto proximal fifth of maxillary. A 
similar narroAv band anteriorly in lower jaw. Very broad patches of similar but 
slightly stifler teeth are present on tongue, Ammer, and palatines. Eye less than snout, 
6 in head, nearly equaling the narrow interorbital width. Gill-rakers very stiff and 
bony, the longest four-fifths diameter of eye; 7 + 17 in number, the one in the angle 
reckoned with the vertical limb. They bear on their inner margins two rows of very 
short weak teeth, Avhich do not make them appreciably rough. 
Fully developed rays, D. 12; A. 11; Lat. line, 100. 
* The vertical from last ray of anal traverses the posterior third of base of adipose dorsal. This 
is the only respect in which onr specimens fail to agree with Richardson’s description. The latter 
states that the adipose lin is located “about its own breadth posterior to the anal,” but this can prob- 
ably be accounted for by the nature of the type, Richardson’s descrijition being taken from a stuffed 
skin. 
