The Lamprey. 
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THE SAW-FISH. (Tristis antiquorum.) 
This fish is found in the European and Atlantic seas. 
Its body is flattened anteriorly with four or five branchial 
openings below on each side ; two spiracles behind the 
eyes ; no anal fin ; the head prolonged into a depressed 
bony beak, with strong pointed spines on each side ; the 
lips are rough and sharp like a file, supplying the place of 
teeth. With its formidable weapon, which resembles a 
toothed saw, this fish attacks the largest whales, and in- 
flicts very severe wounds. The colour of its body is 
of a grejnsh brown above, and paler below; its length 
about fifteen feet, the saw being about a third of the 
whole. 
THE LAMPREY. (Petromyzon mminus.) 
The Lamprey belongs to the last family of cartilaginous 
fishes, and is one of the lowest in the scale of vertebrated 
animals. It grows to the length of about three feet, 
although the British species, with which we are best ac- 
quainted, seldom exceeds twelve inches. To avoid the 
constant muscular exertions necessary to prevent their 
being carried away by the current, they attach them- 
selves by the mouth to stones or rocks, and hence are 
called Petromyzon, Stone-suckers. The Lamprey, although 
