494 COROPHIIDJE. 



Astacvs Uncarts. PENNANT, Brit. Zool. Edit. 1777, iv. p. 17. pi. 



xvi. fig. 31. 



Onicus volutator. PALLAS, Spec. Zool. ix. p. 59. tab. iv. fig. 9. 



Cancer grossipes. LINN.&US, Syst. Nat. ii. p. 1055. 



THIS species has the eyes small and round. The 

 superior antennae are about one-fourth of the length of the 

 animal ; the first joint of the peduncle has the inner 

 margin crenulated. The inferior antenna are very 

 powerful, and in the male are longer than the animal 

 itself; the penultimate joint of the peduncle being 

 armed upon the inferior distal extremity with a strong 

 tooth, which appears to assist considerably in holding 

 any object when the extremity of the antennae is folded 

 upon itself; this organ appearing to possess the strongest 

 prehensile power, and being no doubt used as a weapon 

 of offence in its battles with other animals in its struggle 

 for existence. The first pair of legs are not powerful 

 organs, being simply subchelate. The second pair have 

 the wrist as long as the hand, inferiorly dilated, and 

 furnished with one or two longitudinal rows of long 

 hairs ; the hand is not so wide as the wrist, and is 

 furnished near the carpal articulation with a diagonal 

 row of long hairs ; the finger is narrower than the hand, 

 and is short, sharp, and slightly curved. The first two 

 pairs of walking legs are moderately long, and terminate 

 in long, straight fingers ; the next two are short, and the 

 last is nearly as long again as the two immediately pre- 

 ceding. The natatory appendages have the basal joints 

 very short and broadly developed. The caudal ap- 

 pendages are also short, the last scarcely reaching beyond 

 the extremity of the telson. 



The colour of the animal is grey, mottled with black 

 stellated markings, appearing to assimilate very nearly 

 to the colour of the soil which it inhabits. It dwells in 



