54 STALK- AND SESSILE-EYED CRUSTACEA 
above. Anterior feet of male short but stout, sub-equal, hand punctate, 
shorter than breadth of carapace, along upper margin to finger much 
shorter than high, fingers much gapmg. Posterior feet rough hairy. 
Length 224 lines ; breadth 28 lines. (D.). 
Auckland (Heller); Fiji Is. (Dana). 
The species of this genus are separated by characters of very slight 
importance, and perhaps only one species inhabits the whole Asiatic 
region. 
Sub-Tribe IV. OxysToMATa. 
Orbiculata, Latr. (part) Fam. Nat. p. 271, (1825). 
Oxystomes, M. Edw. (part) Hist. Nat. Crust. 1, p. 265, (1834). 
Leucosoidea v. Oxystomata, Dana, U.S. Explor. Exped. xii, Crust. 
part i, p. 389, (1852). 
Carapace varying greatly in shape, transverse, arcuate anteriorly, or 
sub-globose. Branchie 7—9 in number. Antennary region very 
small, antenne minute. Hpistome rudimentary. Buccal cavity more 
or less triangular in outlme, produced and narrowed anteriorly. 
Efferent channel passing out at the middle of the palate, which is 
produced forwards. Male genital appendages inserted in the basal 
joint of the fifth pair of legs. 
Family I. CALAPPID. 
Calappiens, M. Edw. (part) Hist. Nat. Crust. ii, p. 100, (18387). 
Calappide, Dana, U.S. Explor, Exped. xiii, Crust. part i, p. 390 
(1852). 
Afferent canal to the branchiw entering behind the pterygostomian 
regions. Genital appendages of the male exserted from the base of 
the fifth pair of legs. Terminal joints of the external maxillipeds not 
concealed beneath the second and third joints. 
CALAPPA. 
Calappa, Fabr. Ent. Syst. Suppl. p. 845, (1798); M. Edw. Hist. 
Nat. Crust. il, p. 102, (1837); Dana, U.S. Explor. Exped. xiii, Crust. 
part 1, p. 890, (1852). 
Carapace very convex, broad behind, arcuate in front, with the 
latero-posterior margins produced over the ambulatory legs, and form- 
ing large vaulted lateral expansions, Terminal joints of the external 
