DORIPPE. CRUSTACEA. 159 



H. spimfrons, Leach. Shell anteriorly spinous ; sides anteriorly be- 

 set with small spines ; hinder thighs with three interior spines. 

 1^ inch long, 1 broad. Mediterranean sea Zool. Mis. ii. pi. 88. 



Gen. 40. DoRirpE, Fab. Cancer, Lin. 



Exterior antennae setaceous, inserted above the intermediate ones; 

 third joint of the exterior feet-jaws narrow, elongated, and 

 pointed ; forceps small, short, and equal ; the other feet very 

 long and compressed, the third pair largest ; the two last 

 pairs inserted on the back ; shell depressed, truncated and 

 spinous before, and sinuous behind, with the surface marked 

 by elevations ; eyes small, lateral. 



D. lanata, Lat. Body covered with a reddish down, trigonal, uni- 

 dentate on each side ; front quadridentate ; feet hairy. Inhabits 

 Mediterranean sea Plancus, Conch, pi. 5, fig. 1. 



Gen. 41. RANINA, Lam. 



Four short antennae, the two intermediate ones with thelast joint 

 bifid ; shell wedge-shaped or oblong, truncated anteriorly ; 

 tail small, articulated, ciliated on the margin ; ten feet, the 

 two anterior almost didactyle, the others terminated by flat- 

 tened oval plates or fins. 



R. serrata, Lam. (C.raninus, Lin.) Shell oval or wedge-shaped, 

 flattened, truncated before, with seven or nine teeth ; arms strong- 

 ly dentated. Inhabits Indian seas Humph. Mus. pi. 7> fig. T. V. 



SECTION II. MACROURA. 



The body in this section is generally narrower and more elongated than in the 

 animals of the preceding division, with the upper part of the post-abdomen convex 

 and often carinated. The antennae are also longer, the intermediate ones projecting 

 equally with the others, and terminated by two or three setaceous filaments. The 

 exterior feet-jaws or pedipalpi have the form of slender feet or palpi. The form of 

 the anterior feet is various. In some the first pair, or the first two pairs, and even 

 the third pair, are didactyle or terminated by forceps ; in others none of the feet are 

 didactyle ; and sometimes even the anterior feet are without claws. The peduncles of 

 the eyes are always very short ; the inferior appendages of the post. abdomen gene- 

 rally larger. The shell is also weaker than those of the preceding section, and flexi- 

 ble in many species. The Macroura have vesicular branchiae, bearded or hairy, ap. 

 proximated in bundles above the feet, and accompanied by a membranous and vesi- 

 cular appendage, in the form of an elongated bag. The last segment of the post- 

 abdomen has o-n each side a process forming a kind of spreading fin. The post-ab- 

 domen is composed in both sexes of seven distinct segments. 



FAMILY I. HIPPIDES. 



The two anterior feet tapering to their extremity and pointed, 

 sometimes terminated by a monodactylous hand, with or with- 

 out a claw ; the six following with generally the last joint in 

 the form of a fin, and the last two short and folded back ; last 

 abdominal segment elongated, and the preceding with a folia- 

 ceous appendage on each side. 



Gen. 42. ALBUNEA, Lat. Cancer, Lin. 

 Intermediate antennae of one filament, longer than the lateral 



