REPORT ON THE CRUSTACEA MACRURA. 173 



moderately long cilia ; the terminal joint is short and reaches to the extremity of the 

 scaphocerite, and nearly as far as the distal extremity of the rostrum ; the flao-ellum is 

 slender and free from hairs, and is four or five times as long as the peduncle. 



The metope is smooth, and terminates in a deep ante-oral ridge or epistoma. The 

 mandibles (PL XXII. d) are large and powerful, have a serrate margin on the psalisi- 

 form blade, and support a triarticulate synaphipod, of which the terminal joint is broad 

 and hirsute. 



The first siagnopod (e) is three-branched, the two inner branches being foliaceous and 

 of extreme tenuity, the first being fringed with soft cilia on the inner margin, and the 

 second with short, stiff, tooth-like spines ; the third branch is biarticulate, narrow, and 

 cylindrical, fringed with hairs on each side, and supports a second joint, which is flexed 

 and turned outwards. The whole is in close contact with the mandibles. 



The second siagnopod (/) is large, broad, and foliaceous, consisting of three branches, 

 two of which are longitudinally divided, and a broad mastigobranchial plate that 

 reaches forwards as far as the other branches, and only a little behind the basal articu- 

 lation. 



The third siagnopod (g) is three-branched, and supports a long mastigobranchial 

 plate. The first branch is broad, of great tenuity, foliaceous, and thickly fringed with 

 cilia ; the second is biarticulate, cylindrical, and fringed with cilia ; the third branch 

 consists of a long basal joint, fringed with many cilia on the outer margin only, and 

 supports a multiarticulate flagellum. The mastigobranchial plate is long and tapering, 

 the distal mararin serrate, and the surface having numerous lona; fine hairs. 



The first pair of gnathopoda (h) is six-jointed, the dactylos being absent or repre- 

 sented by several short, stout, tooth-like spines ; the propodos is short and obtuse, the 

 carpos broad, much more so than the propodos or meros ; the ischium is long and broad, 

 straight on the outer, and arched on the inner side, which is fringed with marginal hairs, 

 and submarginal tufts of hairs ; the basis carries an ecphysis, of which the extremity 

 for more than half its length is multiarticulate ; the mastigobranchial plate is long, 

 tapering, and sparsely covered with long delicate hairs, and the podobranchia is short 

 and small, less than one-third the length of the mastio-obranchia. 



The second pair of gnathopoda ((') is long and slender, more especially the three distal 

 joints ; the meros and ischium are broad, subequal in length, and armed on the inner side 

 with a row of short obtuse teeth, mingled with numerous fine hairs ; the basis supports 

 a slender uni-articulate ecphysis, and the coxa carries a mastigobranchia with a long podo- 

 branchial plume. 



The first pair of pereiopoda (PI. XXI. k) is long, cylindrical, and chelate. The ischium 

 is short, and articulates freely with the meros ; the meros is long, and articulates freely 

 ■with the carpos ; the carpos is short, continuous, but with a slight articular movement 

 with the propodos, which is cylindrical at the base, and becomes horizontally flattened 



