STOMATOPODA. 505 



thoracic feet are turned forwards as maxillipeds, the three posterior 

 separate from them and biramous. The swimming feet on the 

 strongly developed abdomen bear branchial tufts, and the sixth 

 pair forms, with the telson, a caudal fin. 



The Stomatopoda are a small number of closely related species 

 inhabiting in the adult state coral reefs and sandy shores in the 

 tropical and temperate regions of the globe. Though sharply 

 separated from other Malacostraca, they present features of 

 resemblance with the Amphipoda, Isopoda and Cumacea on the 

 one hand and with the Decapods on the other. 



FIG. 309. Squilla mantis (after Claus). A', A" first and second antennae ; B'-B'" the 

 6th-8th thoracic legs (biramous) ; Kf, Kf" first and second maxillipeds. 



The integument is thin and flexible. The five anterior seg- 

 ments of the thorax are crowded together behind the elongated 

 cephalic region, and the dorsal shield is almost entirely a 

 cephalic structure though overlapping the anterior segments 

 of the thorax. It is less extensive in the adult than in the 

 larva. The appendages of the five anterior thoracic segments 

 are directed forwards about the mouth, and thus have 

 the character of maxillipeds. Those of the three posterior 

 thoracic segments are directed downwards. In the division 

 of the thoracic legs into these two groups the Stomatopods 

 resemble the Amphipods (Fig. 309). 



The abdomen is large and powerful, and lodges several of the 

 organs which in other Malacostraca are situated in the thorax. 



The anterior region of the body is distinct from the dorsal 

 shield and divided into two small movable segments, the 

 anterior carrying the stalked eyes, the posterior the first 

 antennae. The latter terminate in a flagellar endopodite and 



Isopoden, Cumaceen and Stomatopoden, Erg. der Plankton-Expedition, 

 Kiel, 1895. Orlandi S. Sulla struttura del. intestine del Squilla mantis, 

 Atti Soc, Ligustica, xii (1901), 2, p. 112. 



