South African Crustacea. 61 



may rest contentedly in Trischizostoma, unless that genus be 

 separated from Guerina. They have the monstrous eyes and huge 

 peculiar first gnathopods which are so remarkable alike in T. raschii 

 and G. nicceensis. They have the mandibles of the latter, the first 

 maxillae of the former. As to the first joint of the palp in the 

 maxillipeds, they agree better with the latter than the former. But 

 they differ from both in the shape of the side-plates to the second 

 gnathopods and the first and second perseopods, in the second joint 

 of the fifth perasopods and still more in the flattened leaf-like 

 appearance of the sixth joint, and lastly in having the telson divided 

 for two-fifths of its length. The specimens are certainly of the male 

 sex, and perhaps not fully adult, as the torsion of the first gnathopods 

 had not been effected or not completed. To have three genera for 

 three (or possibly only two) species, which share characters so very 

 notable, while the real or supposed differences refer chiefly to 

 degraded mouth-organs, seems to me to be for the present un- 

 advisable. 



In the new species the first maxilla has a well-pronounced inner 

 plate of slight texture, an outer plate with five spine-teeth on the 

 apex, four of them much curved, and a small one- or two-jointed 

 palp tipped with a long seta. For T. raschii, Boeck describes the 

 first maxilla as consisting apparently only of the outer plate ; 

 Bovallius endows it further with a one-jointed palp, Sars alone 

 awarding to it a slender unarmed inner plate together with " a very 

 minute, but distinctly biarticulate " palp. The supposed absence 

 of the inner plate cannot, therefore, be relied on for distinguishing 

 Costa's species from Boeck's. It is clear that this small pellucid 

 structure sometimes escapes observation under the difficulties of 

 dissection. That the small palp is at first one-jointed, and later on 

 biarticulate, is far from impossible. Bovallius gives the telson of 

 the young male, " probably just out from the incubatory pouch of 

 the mother," as having the apical margin excavate. Boeck also 

 speaks of the telson as apically divided, but probably by a misprint, 

 as his Latin text says that it is apically rounded. That the new 

 species with an incised telson should stand in the same genus with 

 one (or two) species in which the telson is whole-rimmed, agrees 

 with what is found in another Lysianassid genus, Onisiinus, Boeck. 



TRISCHIZOSTOMA REMIPES, n. sp. 



Plate XXXIV. 



The head is almost entirely covered by the large dark eyes, 

 broadest above, meeting in the medio-dorsal line, and leaving 



