CRASS, ETC. 



passes through no metamorphosis. The body is com- 

 pressed, the rostrum distinct from the carapace. 



Order V. Fourteen-footed Crustaceans (Tetra- 

 decapoda]. In this order are the beach-fleas (Fig. 94), so 

 common among the weeds ; the pill-bugs and others living 

 in salt and fresh water. The Idotea phosphorea has an 

 acute tail-piece, and mimics the eel-grass and fucus with 

 its green, gray, and yellow col- 

 ors, at night gleaming with 

 vivid phosphorescence. They 

 live under stones and rock- 

 weed, and when touched curl 

 into a ball. The eggs are held 

 in a little brooding cavity un- 

 der the thorax between the 

 legs. Many species of Podo- 

 cerus and others build curious 

 nests in which they take shel- 

 ter. A gigantic amphipod has 



FIG. 94. Sand-hopper (Talitrus 

 sal tat or). 



FIG. 95. Mantis shrimp 

 (Squilla mantis'). 



two enormous faceted eyes that entirely cover the head. 

 The Arcturus, from Arctic seas, mimics sea-weed with its 

 long antennae, and carries its young about on its back or 

 feelers. The Squilla, or mantis shrimp (Fig. 95), repre- 

 senting Order VI, Stomapoda, is an interesting form ; the 

 gills are attached to the base of the under abdominal feet. 

 They burrow in the sand below tide-water. 



