/. CRUSTACEA: 1SOPODA. 



441 



into the skin. The Bopyridae live in the branchial chamber of shrimps. 

 Cryptoniscus is a shapeless sac which attaches itself to the stalk of Sacoii- 

 lina (p. 426), and, after causing the death of this parasite, uses its network 

 of roots ' for its own nourishment. The Entoniscidae (fig. 453) attack 



FIG. 453. Entoniscus porcellance. (From Gerstacker, after Miiller.) A, male; 2?, female; 

 C, heart; he, liver; la, brood lamellae; ov, ovary. 



FIG. 454. J, Idotea irrorata *; B, Limnoria lignorum *; <7, ^ga psora * (' salve bug '); 

 D, Leptochela algivola* (After Harger.) 



Decapoda and, pressing the skin before them, penetrate the interior. Their 

 strange shape is largely due to the lobe-like brood lamellae. They are 



