14 MARINE AND FISHERIES 



5 GEORGE v., A. 1915 

 Ameiurus lacustris, Walbaum. 

 (Great Lake catfish) 

 (Fig. 5) 



This species appears to be present along the main shore of Georgian Bay only 

 in small numbers. It is said to be taken frequently in the Magnetewan River 

 at Byng Inlet. A single specimen was taken near the biological station at Go 

 Home Bay, in 1907, the weight of which was 37 lbs. In this region it occurs chiefly 

 inland, being abundant in Flat Rock Lake and in the Musquash River immediately 

 above the lake. The specimens taken here are commonly from 5 to 15 lbs. in 

 weight. It may be taken in the darker water by ordinary rod-fishing during the 

 day. 



Length 2 feet or more. Body moderately elongated, the trunk very heavy 

 forwards and laterally compressed towards the tail. Depth 4-2 to 5. Head 

 broad and depressed, its length 3*2 to 4 in the length of the body. Eye small, 

 8-2 to 11 in head. Four pairs of barbels, of which the maxillaries are as long 

 as or but slightly shorter than the head. Coloration uniformly dark ashy above, 

 lighter below. Dorsal fin with 1 spine and 6 soft rays. Anal fin with 23 to 27 

 rays, its base 3-4 to 3*5 in the length of- the body. Pectoral fin with 1 spine 

 and 8 soft rays, the length of the spine 2-3 to 2'5 in that of the head. Fins all 

 dark, except the ventrals, which are ashy at the tips. 



The stomachs of several specimens examined contained nothing but crayfish. 

 No reports are available concerning the spawning habits; but since the fish is not 

 seen in shallow water at any time, after the manner of the smaller catfishes when 

 spawning, it is assumed that the eggs are deposited in deep water. 



Ameiurus nebulosus, LeSueur. 

 (Common or brown bullhead) 



The small catfishes of Georgian Bay show considerable variation, but an ex- 

 amination of a large number of specimens indicates that there is but one species. 

 Specimens from these waters are rarely more than 12 inches in length, and the 

 general coloration, doubtless associated with the transparency of the water, tends 

 to dark grey and black above with ashy shades below. The cloudy markings 

 are present but concealed. 



The fish is extremely common in all shore swamps and Ig-rger inland lakes of 

 a swampy character, but is taken as a rule only at night. Throughout the summer 

 the food consists almost wholly of Mayfly larvae, for which the fish burrows in the 

 mud of the bottom. 



The following are the critical measurements of Go Home specimens indicating 

 the reference to A. nebulosus. Depth of body 3*8 to 5, usually 4'1. Head 3 '2 

 to 3*7, usually 3-4. Pectoral spine in head 2*1 to 2-5, usually 2-3. Rays of 

 anal fin 21 or 22; length of anal base in length of body 4'1 to 5., usually 4-5 (25 

 specimens). 



