THE CRUSTACEA OF NEW JERSEY. 365 



Super-Family HIPPIDEA. 



The Sand Bugs. 



Carapace ovate or subquadrate, comparatively smooth, regions 

 ill defined and front broad. Cornese of eyes small. Generally 

 first antennae strongly developed, with one flagellum elongate 

 and other of moderate size or absent. Second antennae usually 

 with short flagellum and massive peduncle of four or five joints, 

 with or without movable acicle on second. Third maxillipeds 

 moderately broad, sub-operculiform. Walking-legs with flat- 

 tened terminal joint, fifth pair slender and filiform and folded 

 under preceding pair. Sterna of trunk linear. Pleon partially 

 extended, with telson large, longer than broad, and preceding 

 segment carries pair of biramous lamellar appendages not so ar- 

 ranged as to form rhipidura. Males have no appendages to pleon 

 but those of penultimate segment. 



These animals live in the shallow waters of tropical and sub- 

 tropical seas. Two families are usually admitted. 



Family HIPPID^. 

 The Sand Bugs. 



Third maxillipeds sub-operculiform, with broad fourth joint, 

 and exopod absent. First pair of legs subcylindrical, not chelate. 

 Telson elongated and lanceolate. 



Genera three or four. The non-chelate character of the an- 

 terior legs, and the ovate contour of the carapace render them 

 especially adapted for moving quickly about in the shifting loose 

 sands of surf-beaten shores. 



Genus EMERITA Gronow. 



The Sand Bugs. 



Emerita Gronow, Zoophylac, 1763, p. 234. Atypic. (Type Cancer emerita 

 Linnseus. See J. E. Benedict, Bull. U. S. F. Com., XX, 1900 (1902). p. 

 138.) 



