1 66 ISOPODS. 



THROAT-FOOTED CRUSTACEANS. ORDER L^EMODIPODA.* 



The body of these creatures is slender and elongated, and 



composed of eight or nine 

 segments. The four front 

 legs, which are always 

 the largest, are attached 

 to the neck, and are ter- 

 minated by a prehensile 

 hook. The hinder legs 

 are shorter and their ar- 

 mature more feeble. The 

 females carry their eggs 

 between the second and 

 third segments of the 



FIG. 168. CAPRELLA. 



body, in a little pouch 



formed of scaly pieces. The species are all marine. Some of 

 them live amongst sea-weeds, upon which they crawl, much after 

 the manner of the caterpillars called Loopers. They are, how- 

 ever, likewise able to swim. Others are found to live parasitically 

 upon whales, a circumstance which has obtained for them the 

 name of Whale-Lice ; they have likewise been seen upon the 

 mackerel. 



EQUAL-FOOTED CRUSTACEANS ORDER ISOPODA-J- 



Differ from the preceding in many important particulars. The 

 two anterior feet are never annexed to the head, but are appended 

 to a distinct segment, and furnished with simple pointed claws. 

 In some species which are terrestrial in their habits, two of the 

 antennae (the middle pair) are almost obliterated. The females 

 carry their eggs attached to the under part of their body, either 

 enclosed by scaly plates or lodged in a membranous pouch. The 

 young are born in every respect resembling their parents, and 

 only change their skin as they increase their size. The greater 

 number live in the water, and those which reside on the land 

 require a certain degree of dampness to enable them to respire. 

 We select, as an example of this Order, the redoubtable 



Boring Shrimp (Limnoria terebrans], so called from its habit of boring into 

 wood submerged beneath the surface of the sea. Although this little creature is not 



* \atfjios, laimos, the throat ; <u's, dis, tunce ; TTOVS, T0o6s, pous, podos, afoot. 

 t <'fOs, isos, equal ; -TTOVS, a foot. 



