260 



ORDER L^EMODIPODA ; CAPRELLA. 



of a portion of this Order are parasitic in their habits ; attaching 

 themselves to the bodies of Fishes ; and having the mouth more 

 adapted for suction. 



ORDER IV. L^MODIPODA. 



796. The Crustacea of this Order resemble the preceding in 

 the conformation of the respiratory organs ; but differ from all 

 the other Edriophthalma, in the want of development of the 

 abdomen. The number of legs varies considerably in the different 

 species. The body is composed (with the head) of eight or nine 

 segments, of which seven may be furnished with members ; but 

 not unfrequently some of the appendages are undeveloped. This 

 Order is divided into two Sections, according to the form of the 

 body; the Filifor- 

 mia, having the 

 body long and 

 thread-like, and the 

 legs also long and 

 slender (Fig. 483); 



Whilst in the Ovalia, FIG. 483. CAPRELLA PHASMA. 



the body is shorter 



and broader, and the legs shorter and stouter (Fig. 484). Of 

 the former group, the Caprella phasma is a characteristic exam- 

 ple ; it is found among marine plants, 

 creeping along in the same manner as the 

 Geometer, or Looper-Caterpillars ( 700), 

 often bending itself back with great rapidity, 

 and applying its antennae to various parts of 

 the body. It has five pairs of legs, of which 

 the second is the largest; these are not disposed, 

 however, in a regular, but in an interrupted 

 series, the second and third segments of the 

 thorax having only the respiratory vesicles. 

 In an allied genus, there are also ten legs, disposed in a con- 

 tinuous series ; and in another, all the fourteen are developed. 



FIG. 484. CYAMUS BA- 



