Ie ee AR Vi RE v4 
(Petromyzon marinus) 
In May and June the lamprey ascends our rivers to spawn. A 
number of these are frequently caught in the salmon fishers’ nets 

FIG, 236.—Mouth of a Lamprey, showing the sucker and teeth. Half life size. 
on the Tay, and are mostly from 24 to 30. inches in length, and 
weigh from 2 to 3 lbs. They are more plentiful in England than 
in Scotland, and are caught for the market. The colour is bluish- 
green with brown blotches, merging into an orange colour on the 
belly. 
The lamprey has a very characteristic mouth. When opened to 
its fullest extent it is quite round and has the tongue well armed with 
numerous teeth (see Fig. 236, which gives a very clear representa- 
261 
