REPORT ON THE AMPHIPODA. 643 



Remarks. — There seem to be many points of affinity between this genus and the 

 genus Glycerina of Haswell. Of the type species, Glycerina tenuicornis, Mr. Haswell 

 veiy kindly sent me a specimen, but the bottle containing it being broken in transit, the 

 specimen was dry when it came to hand, and therefore not well fitted for the observance 

 of minute details. Mr. Haswell states that there is no accessory plate to the mandibles. 

 On this I cannot pronounce any opinion from my own observation. I observed three 

 strong spines in the spine-row, and on the long molar tubercles several (nine or ten) little 

 bright spines of cylindrical appearance standing out, not closely set, surrounded by a fur 

 of cilia ; the spines of the first maxilla run some distance down below the apical margin ; 

 the teeth on the apex of the palp are only seven or eight in number ; the outer plates 

 of the maxillipeds are feebly toothed ; nor are other differences wanting. 



Platamon longimanus, n. sp. (PL XIII.). 



A small rostrum ; lateral lobes of the head produced to a point, forming an equilateral 

 triano-le, dorsal line of the head longer than that of the first pergeon-segment ; postero- 

 lateral angles in the first segment of the pleon rounded, in the second rectangular, in the 

 third acute and upturned ; fourth segment with a dorsal depression, slightly carinate, 

 pointed behind; the sixth segment with lateral ridges on the back, which converge 

 towards the telsou and diverge when they reach its base. 



Eyes not observed. 



Upper Antenna. — First joint very broad, distally projecting over the two next joints, 

 which are very short, the projection being (like the rest of the joint) dorsally sharp, 

 apically rounded ; the flagellum of seven joints, the first tapering, equalling in length the 

 other six united, the cylindrical setae short, in some thirty rows ; a long spine is placed 

 at the distal end of the first joint, a shorter one on the second ; the secondary flagellum 

 slender, of three joints, together nearly equal in length to the first of the primary 

 flao-ellum, the first a little curved, longer than the other two combined. 



Lower Antennw. — First joint not greatly dilated, gland-cone of the second joint long 

 and narrow, third joint short, fourth and fifth joints long, subequal, the fifth the narrower 

 and rather the longer ; flagellum (on one of the antennae) of thirty-five joints. 



Triturating Organs of the stomach present a double very sinuous row of short, 

 somewhat curved spines on one edge, on the other a projecting row of seta-like spines, set 

 as the ornamental pipes of an organ-front often are, with the longest in the middle, those 

 on either side gradually decreasing in size. 



Mandibles. — Cutting edge convex, bent out of shape in the specimen examined, but 

 seemingly with the usual denticle-like prominence above, and the lower apex not divided ; 

 secondary plate of left mandible strap-shaped, rather long, ending acutely, with two 

 teeth above the apex ; spine-row not made out ; dentate crown of molar tubercle very 



