CRABS, ETC. 85 
passes through no metamorphosis. The body is com- 
pressed, the rostrum distinct from the carapace. 
Order V. Fourteen-footed Crustaceans ( 7¢ira- 
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 Jdotea 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 
Fic. 94.—Sand-hopper (Z7alztrus Fic. 95.—Mantis shrimp 
saltator). (Sguclla mantis). 
two enormous faceted eyes that entirely cover the head. 
The Arcturus, from Arctic seas, mimics sea-weed with its 
long antennz, and carries its young about on its back or 
feelers. The Sgué//a, 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. 
