CHAPTER XIX. 
FISHES. 
By 
Cc. W. NASH. 
Tur following list includes all the fishes found 
within a radius of ten or twelve miles from the city 
of Toronto of which I have authentic records. 
MARSIPOBRANCHII. (The Lampreys.) 
PETROMYZIDAE. 
1. Silver Lamprey. Lamper Eel. J. cthyomyzon 
concolor (Kirtland).—The Silver Lamprey is abun- 
dant in Lake Ontario, usually in deep water, but it 
runs up the small streams to spawn in the spring. 
It is a most destructive parasite on the large com- 
mercial fishes, fixing itself to their bodies by means 
of its suctorial disk and causing deep ulcerated 
wounds at the point of attachment, which very fre- 
quently result in death. When spawning they form 
nests in the bed of the stream among cobble-stones 
and pebbles; in these the eges are deposited, after 
which the parent fish all die. After emerging from 
the eggs the larvae burrow in the mud or sand near 
the margin of the stream and there remain in the 
larval condition, blind and toothless for a long period, 
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