186 G. 0. SARS, 



The cephalon about equals in leugtli tlie first 2 segments of mesosome 

 combined. It exhibits dorsally a low keel, and is produced in front to a 

 somewhat flattened, liorizontally projected rostrum of an acute triangular 

 form, and reaching nearly to the end of the basal joint of the superior 

 antennae. Tlie lateral faces of the ceplialon are evenly convex in their upper 

 part, but inferiorly they jut ont on each side to a remarkable spiniform process 

 extending laterally nearly at a right angle to the longitudinal axis. These 

 processes are considerably longer tlian tlie rosti'uiu and terminate each in a 

 sharp point. 



The 4 anterior pairs of coxal plates, extending nearly vertically down- 

 wards, are rather large, being almost twice as deep as the corresponding 

 segments. They are all densely fringed on the distal edge with delicate 

 bristles, and, when the body is curved in the manner usually found in alco- 

 holic specimens, completely overlap each other with their anterior edges, 

 so as to form together on each side a continuous wall, inside which the oral 

 parts, the gnathopoda, and partly also the 2 anterior pairs of pereiopoda 

 may be wholly concealed. When the body is fully extended (see fig. 1), 

 these coxal plates become somewhat separated in their outer part, still 

 forming in their upper part a continuous wall. The 1st pair of coxal plates 

 (see fig. 15) are somewhat narrower than the succeeding ones and slightly 

 curved, with the anterior edge concave, and the outer part somewhat ex- 

 panded, forming in front a narrowly rounded lobe, which, when the animal 

 curves itself, is received just beneath the lateral process of the cephalon. 

 The 2 succeeding pairs of coxal plates (see fig. 16) are nearly of equal size 

 and oblong quadrangular in form, with tlie anterior corner somewhat more 

 projecting than the posterior. The 4th pair (see also PI. II, fig. 4) are not 

 fully as deep as the 2 preceding pairs and but little broader. They exhibit 

 a rather ditferent form, being obliquely truncated at the end, with the 

 posterior edge slightly emarginated in its upper part, and projecting below 

 the emargination as an obtuse angle. 



The 3 posterior pairs of coxal plates are much smaller than the anterior, 

 and successively decrease in size. The 5th pair are scarcely half as dee]) as 

 the 4tli, and, as usual, divided into 2 rounded lobes, the anterior of which 

 is somewhat deeper than the posterior. The 2 last pairs are transversely 

 quadrangular in form. 



The epimeral plates of the metasome are not very large; those of the 

 2 anterior segments are rouuded, those of the last segment obtus-angular. 



In a dorsal view (fig. 2) the body appears very tumid and of a some- 

 what fusiform shape, the greatest breadth, which is fully as great as the 

 height (including the coxal plates) and about equals V3 of the length, oc- 



$H3.-Ma,T. cTp. 1S6. .0 



