502 MR. C. SPENCE BATE [NoV. 24, 



than the rostrum, and hare the secondary ramus rather shorter 

 than the primary. The inferior antennae have the squamiform ap- 

 pendage reaching to the extremity of the rostrum, the lateral den- 

 ticle one-fourth distant from the apex, the flagellum being as long 

 as the animal. The mandibles are furnished with an anteriorly di- 

 rected or rudimentary incisive process, slightly curved, tapering to 

 the apex, and armed with five small denticles. The first pair of 

 pereiopoda are short, robust, and have the excavation at the anterior 

 margin of the carpus deeply lunate, and the anterior process and 

 dactylos fringed at the margin with several broad and flat teeth and 

 a few hairs. The second pair of pereiopoda are scarcely longer than 

 the first, and are more robust than in the preceding species. The 

 remaining pairs are rather longer than the two preceding, and more 

 slender. The posterior pair of pleopoda are rather longer than the 

 telson, which last differs but little from that of the preceding species. 



This description is taken from a female specimen, which is shorter 

 and more robust and gibbous than either of the other species of the 

 genus. The colour of the living animal has not been recorded ; but 

 in a preserved state it is yellowish, blushing into red, mostly so upon 

 the dorsal surface and the posterior segments of the pleon. 



It was captured, with the other specimens in this collection, by 

 Mr. Angas, in Gulf St. Vincent, under the conditions previously de- 

 scribed. 



Genus Anchistia, Dana. 



Anchistia ^sopia. (PI. XLI. fig. 5.) 



*A. rostro supra novem dentibus et duobus infra apud apicem 

 annato. Pleontis tertio segmento in dentem ingentem dorsaliter 

 et posterius producto. 



Having the rostrum nearly straight, armed above vdth nine teeth, 

 the posterior standing near the centre of the carapace, and with two 

 below near the apex. There is also an infraorbital, as well as a post- 

 orbital, and an anterior branchial tooth. The pleon has the third 

 segment postero-dorsally carinated and elevated into a hump-like 

 tooth, being posteriorly produced to a point. The eyes are half as 

 long as the rostrum. The superior antennae have the peduncle as 

 long as the rostrum ; the first joint, being longer than the other two, 

 is broad, squamiformly developed, and armed with two teeth, a large 

 one near the base, and a smaller one near the distal extremity ; near 

 the base, in the position of the auditory organ, unlike that of its 

 near ally Palcemon, there is a distinct otolithe ; the next two joints 

 are short ; the flagella are three, the primary and secondary being 

 fused together for about two-thirds the length of the primary, the 

 secondary being half as long again, and the tertiary being only one- 

 third the length of the primary. The inferior pair of antennae have 

 the squamiform appendage round at the point, furnished with a 

 tooth one-third from the apex, and reaching quite to the extremity of 

 the rostrum — the flagellum being as long as the animal. The man- 

 dibles are of the same form as in Palcemon. The second pair of gna- 



