34 EBV. T. E. E. STEBBING AND JIR. D. EOBEETSON ON 



several small details ; the second joint of the upper antennje is less elongate, the 

 armature of the first giiathopods is slighter, the hand of the second gnathopods is 

 differently shaped, the third segment of the pleon is dorsally curved downwards instead 

 of being posteriorly squared, the telson is longer than broad and less deeply cleft. In 

 general features the two species are remarkably alike, and now that this rather striking 

 genus is found to have a representative in one of our own estuai'ies, it seems singular 

 that it should have first been made known to us from Antarctic waters. 



2. Syeehoe fimbeiatus, n. sp. (Plate V. b.) 



The third segment of the pleon with the lower hinder angles produced into an acute 

 upturned point, the two preceding segments having these angles acute, but only 

 slightly produced. The dorsal denticles apparently present on some or all of these 

 segments were not clearly made out. The sixth segment of the pleon fringed behind 

 with a close-set row of spinules. 



Upper antennm. First joint stout, longer and much broader than the second, which 

 is nearly twice as long as the third ; the flagellum longer than the peduncle, the first 

 joint as long as the first of the peduncle, and as long as the six following joints united, 

 armed with a brush of long filaments ; the secondary flagellum three-jointed, the small 

 third joint not quite reaching the end of the second joint of the principal flagellum. 



Lower antennae. The first joint broader than long, overlapping the little acute gland- 

 cone of the second joint, the third joint a little longer than broad, the fourth longer 

 than the three preceding united, rather shorter than the fifth, each of these two carrying 

 tufts of setules; the flagellum very slender, longer than the peduncle, consisting 

 probably of ten or twelve joints, of which eight were present. 



Upper Up. The central part of the distal margin forms an almost semicircular lobe, 

 which in the dissection was folded back, but whether this may be its natural position 

 or only accidental, could not be determined. 



Mandibles. Cutting-edge having two teeth and a smooth border on the left mandible, 

 on the right having only the two teeth ; the secondary plate small with four teeth, 

 which are blunt on the left, and delicately sharp on the right mandible ; the molar 

 tubercle broad and strong ; the first joint of the palp longer than broad, the second 

 joint elongate, slightly curved, with four groups of setse, the third joint broken, 

 probably very short. 



First ma.viUw. The palp has on the apex five spines and one spine on the outer 

 margin below the apex. 



Second mam'Uce. The inner plate appears to be broader than the outer, both plates 

 carrying numerous long spines. 



Maxillipeds. Inner plates broad, reaching a little beyond the first joint of the palp, 

 the inner margin produced into a small distal tooth, the distal part of the plate 

 bordered with nine plumose setae ; the outer plates not quite reaching the end of the 



