WORMS. 157 



Another species very common on the sea-shore, under 

 stones, is much shorter than the one just described. It has 

 two rows of oval scales along the back, and the mouth is fur- 



FIG. 144. A COMMON SEA- WORM. 



nished with powerful jaws, which work up and down. When 

 they are placed in alcohol these jaws generally protrude. 



143. Some species have a curious way of protruding 

 their oesophagus when they seize their food, at the end of 



FIG. 145. A SEA- WORM WITH SCALES. The eyes may be seen, four in number, between the 



forward scales. 



which appear the jaws, like sharp claw-shaped teeth. The 

 following figure shows the anterior end of one of these 

 worms, with the oesophagus protruded, in the act of se- 

 curing its prey. 



Certain other sea-worms build tubes - of mud or sand 

 in which they live, and many of these have bunches of 



