SALMONOIDEyE. 



175 



from the nature of the rapid, rocky streams which it frequents : it is not, however, unlikely 

 that an examination of recent specimens may reveal differences of internal structure sufficient 

 to prove it to be a distinct species. A female specimen of the masamacush, taken in a small 

 lake a little to the northward of the 64th parallel of latitude, on the 16th of August, exhibited 

 the following tints of colour. Back and sides intermediate between olive-green and clove- 

 brown, bestudded with yellowish-grey spots as big as a pea : a few of these spots on the gill- 

 covers. Belly and under jaw white, the latter thinly dotted with bluish-grey. Dorsal and 

 upper lobe of the caudal marked with smaller spots. Irides honey-yellow. Scales rather 

 dull. This individual was twenty- one inches long, its flesh was red, and its roe but little 

 developed. The intestines had the structure usual in the trouts, the caeca were numerous, 

 their insertions occupying about three inches of the length of the canal, the valvules conni- 

 ventes occupied two inches, and there was about an inch of smooth gut next the anus. The 

 liver, small and triangular, had several small incisions on its inferior edge. The rakers and 

 pharyngeal bones were armed with short teeth like velvet pile. 



Dimensions. 





From 



From 



British 





Min 



Ran 



Boothia 



Char. 





River. 



Felix. 







In. 



lin. 



In. 



lin. 



In. lin. 



Length from tip of snout to tip of caudal 



24 







20 



6 



18 3 



„ „ end of central caudal 



rays . 23 



9 



19 



6 



17 7 



,, ,, end of scales on ditto 



22 



2 



18 



2 



17 



„ „ anus 



16 



7 



13 



9 



11 10 



„ ,, beginning of dorsal 



10 



2 



8 



5 



7 7 



„ „ edge of suboperculun 



i . 4 



2 



3 



8 



3 



„ „ nape 



2 



9 



2 



2 



1 11 



„ „ centre of pupil 



1 



6| 



1 



4i 



1 2 



„ ,, edge of orbit 



1 



3 



1 







10} 



„ lower jaw, depressed, to tip o 



' caudal 24 



6 



20 



9 







„ „ edge of subop 



erculum 4 



4 



3 



9* 







„ centre of pupil to edge of subopercu 



urn . 2 



6* 



2 



4| 







„ posterior edge of orbit ditto 



2 



3 



2 



H 







„ of transverse axis of orbit 







9 







8* 



61 



„ vertical ditto .... 







5 







5i 







„ intermaxillary 







7 







5' 



4 



,, labial ..... 



2 



H 



1 



6A 



1 3 



„ lower jaw .... 



3 



l 



2 



5" 



1 10 



„ toothed edge of ditto . 



1 



8 



1 



2 







„ attachment of dorsal 



2 



4 



1 



11 



1 11 



„ longest rays of ditto . 



2 



2 



2 



4| 



2 2 



„ its last ray .... 



1 



1 



1 



4 



1 



„ adipose fin ... . 







H 







5 



7 



„ pectorals .... 



2 



H 



3 



2 



2 4 



„ ventrals ..... 



2 







2 



3 



2 



„ ventral appendages 







H 







7 







„ attachment of anal 



1 



8 



1 



H 



1 3 



„ longest ray of ditto 



2 



4 



2 



2 



2 2 



„ its last ray .... 







9 i 







11 







„ lobes of caudal 



3 



6 



3 



8* 







„ longest rays of ditto . . . 



2 



6 



3 







2 7 



,. its central ray (from end of scales) 







7* 



1 



4f 



1 5 



Depth of caudal fork .... 











1 



1 



7 



Distance between anus and tip of caudal . 



7 



10 



7 



4 



6 



„ anal and lower tip of ditto . 



6 







5 



n 







„ adipose and upper tip of ditto 



5 



5 



5 



H 







Depth of body at the dorsal fin . . . 



3 



6 



3 



4 



3 6 



Breadth of occiput .... 



1 



n 



1 



6 







,, between the orbits . . 



1 



5 



1 



1 







