108 CRUSTACEA. 



FAMILY PEKICERID^E. 



SUBFAMILY PERICERIK&]. 



PERICERA TRIGONA. 



Feminae : Carapax bene triangulatus, triangulo equilaterali, spind pos- 

 tero-laterali longd, crassd, camplanatd; super fide supra infraque breviter 

 densissim&que villosd, villis defrictis vero nitid,e porcelland; spinis dor- 

 salibus duobuSj und mediand, cdterd cardiacd; roslro mediocri, cornu- 

 1ms divergentibus ; spind prceorbitali perbrevi, subacutd. Regio ptery- 

 goskmiana uni-spinosa. Articulus pedum Btitis minuie tuberculatus 

 et apice plerumque spinoso-productus ; manu tenui, digitis omnino 

 contiguis. 



Female: Equilaterally triangular, postero-lateral spine long, very 

 stout, flattened; upper and under surface dense and short villous, 

 on removing the villous coat, shining porcelainous ; back with two 

 median spines of moderate size, one to the medial region, one to the 

 cardiac; beak of moderate length; horns divergent. Prseorbital 

 spine very short, subacute. Pterygostomian region with a single 

 tooth. Third joint of feet minutely tuberculous, and the apex for 

 the most part prolonged and subacute; hand slender, finger and 

 thumb in contact within. 



Plate 3, fig. 4 a, animal (female), natural size; b, under view of 

 head; c, female abdomen, enlarged two diameters; d, hand of female, 

 ditto. 



Feejee Islands. 



Length from tip of beak to posterior apex, one and one-fourth 

 inches; breadth across from tip to tip of lateral spines, one and one- 

 fourth inches; breadth across the eyes, half an inch; distance between 

 tips of beak, one-sixth of an inch ; distance between stomach and car- 

 diac dorsal spines, four lines; and the same between the cardiac spine 

 and the posterior apex. 



