160 CRUSTACEA. DEC APOD A. 



ones, and inserted under the eyes ; first pair of feet terminated 

 by a triangular claw ; shell oval, slightly convex, narrowed 

 posteriorly and truncated before ; abdomen short, and the last 

 joint ovoid. 



A. symnista, Fab. Shell subcylindrical, truncated, ciliated., and ser- 

 rated anteriorly. Inhabits Indian seas. Herbst, pi. 22, fig. 2. 



Gen. 43. HIPPA, Lat. 



Intermediate antennae bifid, the lateral ones much longer and 

 bent, plumose on the exterior side, with the base covered by 

 a dentated scale; anterior feet terminated in an oval compres- 

 sed plate ; third joint of the exterior feet-jaws very large, co- 

 vering the mouth ; shell oval, slightly gibbous, and truncated 

 at both extremities ; abdomen terminated by a long triangu- 

 lar segment, with a ciliated appendage at its base. 



H. emeritus, Lat. Shell finely wrinkled transversely, with three 

 teeth on the anterior margin ; legs hairy. Inhabits coasts of Bra- 

 zil. Herbst, pi. 22, fig. 3. 



Gen, 44. REMIPES, Lat. 



Lateral and intermediate antennae short, almost of equal length, 

 slightly bent ; exterior feet-jaws like small arms with a strong 

 hook at the end ; first pair of feet terminated by pointed 

 plates ; the others with ciliated pointed fins. 



R. testudinarius, Lat. Shell oval, finely wrinkled above, with five 

 teeth before, of which the intermediate three are shorter than 

 the lateral ones. 1 inch long. Inhabits coasts of New Holland. 

 Cuv. Reg. An. iv. pi. 12, fig. 2. 



FAMILY II. PAGURII. 



Two anterior feet didactyle, the tarsi of the following four pairs 

 long and pointed ; last four pairs smaller than the others, and 

 terminated in a small forceps or bifid portion, or by a toe or 

 pointed hook ; lateral appendages of the penult segment ge- 

 nerally fleshy ; shell slightly crustaceous. 



The animals of this family are parasitical, and live for the most part in empty uni- 

 valve shells, or in holes in rocks. 



Gen. 45. BIRGUS, Leach. Cancer, Lin. 

 External antennae with the last joint of the peduncle crested ; 

 abdomen crustaceous ; tail two-jointed, crustaceous, the first 

 joint with an appendage on each side ; fourth pair of legs 

 didactyle ; shell in form of a reversed heart, marked above 

 with an impression like an X. 



B. latro, Leach. Large, and of a fine red colour ; rostrum pointed ; 

 forceps red, the left larger than the right, and furnished with 

 strong teeth ; the three following pairs of feet dentated on the mar- 

 gin, and marked with undulated spots. Inhabits Indian coasts, in 

 clefts of rocks, going ashore at night to feed. Herbst, pi. 24. 



