REPORT ON THE CRUSTACEA MACRURA. 659 



inner is slender at the base and tapers gradually to the extremity, and is nearly equal 

 to the length of the animal ; the outer is broad and flat at the base, gradually 

 narrowing it becomes cylindrical, and tapers to the extremity, and it is a little longer 

 than the inner. The under surface of the flattened portion is longitudinally channelled 

 and is furnished with a series of membranous cilia. 



The second pair of antennae supports a small and not very conspicuous phymacerite, 

 a small sharp tooth at the distal angle, and a scaphocerite which reaches to about half 

 the length of the rostrum, and has the outer margin straight, thick and rigid ; and 

 separated from the squamous plate by a longitudinal channel. It is armed at the 

 extremity with a sharp tooth that extends a little beyond the squamous portion, which 

 somewhat suddenly enlarges at the base and then gradually narrows to the distal 

 extremity, where it reaches beyond the base of the tooth on the outer margin. The 

 inner margin is fringed with long ciliated hairs ; the outer is smooth. 



The mandibles are furnished with a hollow and broad apophysis, the outer surface of 

 which is exposed and covered with a mat of short, fur-like hairs ; the molar process is 

 cylindrical, and projects at a right angle to the apophysis, and the psalistoma is produced 

 from the curve, near which also springs the synaphipod ; they lie close together and 

 assume a similar appearance, the contiguous margins being uniform and in contact ; the 

 former is fixed and tipped with two or three teeth, while the synaphipod is broad, thin, 

 curved and triarticulate, the terminal joint being quadrate, and tipped with short hairs. 



The first pair of siagnopoda is three-branched ; the outer branch is curved and 

 bilobed at the extremity, where it is fringed with a few tolerably long, simple hairs ; the 

 second or middle branch is broad and flat, broader at the extremity than at the base, and 

 has the inner margin fringed with ciliated hairs and the distal with short, strong, smooth 

 spines ; the third or inner branch is curved in a direction contrary to that of the outer, 

 the concave margin is smooth, and the convex is fringed with short stiff hairs that 

 gradually increase in rigidity until they become spines at the apex. 



The second pair of siagnopoda consists of three foliaceous branches of extreme 

 tenuity ; the inner branch is bilobed and has the distal margin fringed with hairs, and 

 among those on the basal lobe are a few strong spines ; the median branch is short, 

 Hat, and tapers somewhat suddenly, especially towards the extremity, which forms 

 a blunt point; the outer branch consists of a broad foliaceous plate of extreme tenuity, 

 projecting anteriorly beyond the distal extremity of the inner plates, where it is obtusely 

 rounded off, and posteriorly in a still broader and more rounded process, the entire 

 margin of the plate being fringed with long ciliated hairs, which radiate centrifugally 

 in the same direction. 



The third pair of siagnopoda is three-branched ; the inner branch is broad, flat, 

 squamous and bilobed, each lobe being fringed at the distal and contiguous margins 

 with a thick mat of hairs, closely placed towards the base ; the second branch is 



