REPORT ON THE AMPHIPODA. 1159 



the front margin, followed by two pairs of similar spines at intervals, and an apical 

 group of eight ; just above the centre of the hind margin is a single spine, and on the 

 outer surface not far from the base, distant from either margin, two very long spines are 

 planted (shown in the figure, as seen through the transparent joint). 



Lower Lip. — Both the principal and inner lobes appear to be very slightly ciliated 

 and distally dehiscent, the principal lobes also with the inner margins wide apart for a 

 considerable distance, and having a notched appearance, as if of incipient jointing, on 

 the outer margin ; the mandibular processes rather divergent, the apices rounded. 



First Maxilla;. — The inner plate very small, apically narrow, without any trace of 

 setse that I can perceive (in Cerapus tubalaris, Say, they are, according to S. I. Smith, 

 tipped with one or two setse); the outer plate broader at the base than distally, with 

 nine spines on the slightly convex distal margin, four of which have a little denticle below 

 the furcate top, the other five are longer and have several minute lateral denticles ; the 

 first joint of the palp short ; the second reaching beyond the outer plate, widening a little 

 from the base, with five spine-teeth on the dentate apical margin, and three slender sub- 

 marginal spines. 



Second Maxillae. — The inner plate shorter and narrower than the outer, with some 

 spaced plumose setae on the inner margin, beginning beyond the middle of it, near the 

 apex, which has many long spines closely set ; the spines are longer and more numerous 

 round the broader apex of the outer plate. 



Maxillipeds. — The inner plates not nearly reaching the apex of the palp's first joint, 

 with some seta? on the inner margin, and the subapical spine-tooth, the broad distal 

 margin having three spine-teeth and some slender spines ; the outer plates reaching to 

 about the middle of the palp's second joint, the inner margin for some distance smooth, 

 except for the long slender spines which project beyond it from the outer surface, but 

 near the apex having four spine-teeth, followed by four longer spines round the distal 

 margin ; the first joint of the palp of average length, with two long slender spines on the 

 short inner margin ; the second joint not twice as long as the first, with numerous long- 

 spines on its inner margin ; the third joint subequal in length to the first, the margins 

 almost parallel, the apical border carrying many long spines ; the finger very short, the 

 distal end pointed above, carrying a group of spines, one of which is long and strong, and 

 if reckoned as the nail would make the finger equal in length to the third joint. 



First Gnathopods. — Side-plates very small, rather broader above than below, not 

 contiguous with the following pair. The first joint almost entirely free from the side- 

 plate, widening at once from the narrow neck, very little longer than the hand, the hind 

 margin convex, smooth, the front straighter or a little concave, with setules ; the second 

 joint short, with an apical seta ; the third a little longer than the second, the front and 

 hind margins smooth, slightly convex, the distal margin having an irregular row of long 

 spines planted just above it ; the wrist rather shorter than the hand, distally rather wider, 



