210 BOPYRID.K. 



Fam. BOPYRID^E. 



THIS family (corresponding with the section Epicarides 

 of Latreille, and the Isopodes sedentaires of Milne Ed- 

 wards), although but of small extent, as to the number of 

 the species of which it is composed, exhibits some of 

 the most remarkable modifications of structure amongst 

 its different members, whilst the characters of the group 

 render it a very distinct one amongst the families of 

 which the order is composed. So far as hitherto ascer- 

 tained, the species are entirely parasitic upon the bodies 

 of other crustaceous animals, especially those of the 

 shrimp family and hermit crabs ; species also of the 

 genera Galathea, Gebia, Gelasimus, and even of Mysis, 

 have been found to be infested by them. 



The body, particularly of the female, is in most of the 

 species of a much less firm consistence than in the 

 majority of the order and in their full-grown condition, 

 there is a marvellous difference in the size of the two 

 sexes, the females being very large, ovate, or nearly cir- 

 cular in form, with the segments very indistinct, whilst 

 the males are very diminutive and elongated, with the 

 segments of the body quite distinct.* 



In both sexes the antennae are very short, and more or 

 less rudimentary, consisting of only two or three joints 

 in the Bopyri, but with a more distinctly articulated 

 flagellum in some of the Phryxi. The mouth is very 

 rudimental, consisting in the female and probably in the 



* In this respect these insects offer a marked analogy to the family Coccidce 

 amongst hexapod insects. The female Cocci gi'adually lose their locomotive 

 organs and become inert animal masses, capable only of suction and deposi- 

 tion of eggs, with which the body seems entirely filled. 



