114 A. Alcock — New and Bare Species of Crustacea. [No. 2, 



Mandibles with a two-jointed palp. Exopodite of first maxillse 

 with a small curved non-segmented flagellum. Exteroal maxillipeds of 

 the usual pediform shape. 



Chelipeds equal ; massive in both sexes, but more so in the male. 



Legs stout, compressed ; the first two pairs are about as long as or 

 a little longer than the chelipeds, and end in long stout dactyli : the 

 last two pairs are reduced in length and are chelate, the chelae of the 

 penultimate pair being particularly perfect. 



In the male the first two pairs of abdominal appendages are 

 present and are quite symmetrical : they are uniramous appendages 

 modified for purposes of reproduction. The appendages of the next 

 three somites (3rd -5th) are present on one side only — right or left : 

 hey are minute, or rudimentary and, uniramous. 



In the female the appendages of the first abdominal somite form a 

 small symmetrical uniramous pair. Those of the next four somites 

 (2nd-5th) are present on one side only — right or left : the first three of 

 them are slender biramous appendages, of good size, for carrying the 

 eggs, and are contained within a capacious cup-like brood-pouch formed 

 by a membranous lobe that springs from one side of the fifth somite : the 

 fourth of them is a tiny biramous appendage and is not enclosed in 

 the brood-pouch. 



In both sexes the appendages of the sixth somite are symmetrical 

 biramous swimmerets, placed symmetrically on either side of the tel- 

 son : their rami are slender and falciform. 



The branchial formula is as follows : — 



Somites and 



their 

 appendages. 



IX. ... 



X. ... 



XI. ... 



XII. ... 



XIIL ... 



XIV. ... 



Ir. 5 5 3 13 + Ir. 



[]V.B.— The rudimentary podobranch (?) of the external maxillipeds is a small 

 lobe of the anterior arthrobranch of the same appendages ] 



Each gill consists of two series of broad leaflets. The leaflets, how- 

 ever, are not quite simple, since each one carries, near the tip, a pair 

 of slender filaments large enough to be seen with the naked eye. 



The single species known does not inhabit a shell, but lives 



Podo- 



Ar th robr an chise. 



Pleuro- 

 branchiae. 



Total. 



branchige. 



Anterior. 



Posterior. 



Ir. 





1 







= 2 + lr. 















= 2 











1 



= 3 











1 



= 3 











1 



= 3 



















= 



