310 ZOOLOGY. 



the sharp hook-like legs around the margin of the body. The 

 head has no ej'es nor apiDendages. The male (Pig. 262,0, D) 

 is but slightly modified, is very minute, and is lodged partly 

 out of sight under the ventral plates of the female, vphose 

 body is about five millimeti-es (a fifth of an inch) in length. 



Fig. ^Z.—Arciurus Bajjiai^ with its young clingingto its antenniB. — After Wyville- 

 Tliompson. 



Various species of Porcellio (sow-bugs) live under stones 

 on land ; and allied to Asellns, the water sow-bug, is the 

 marine Limnoria terebrans Leach, Avhich is very injurious 

 to the piles of bridges, wharves, and any submerged wood. 

 The highest Isopods are IclotcBa, of Avhich /. irroratus Say 

 (Fig. 255) is our most abundant species, being common in 

 eel-grass, etc., between and just below tide-marks ; and^rc- 

 turus (Fig. 363, A. Baffini Sabine), from the Arctic seas. 



