47 



Dr. Ortmann adds to the above characters that there are 

 no epipods and exopods on the trunk-legs, and that the 

 rostrum is generally short and flat. There is, however, a 

 small exopod on the first trunk-legs in ^geon cataphractus 

 and some other species. In my History of Crustacea I have 

 followed Spence Bate in saying that " the second maxillipeds 

 end in a rudimentary sixth joint, and the third pair have 

 neither the sixth nor the seventh joint." Spence Bate's own 

 expressions are, " First pair of gnathopoda without a 

 dactylos, and the propodos reduced to a rudimentary 

 condition. Second pair having neither dactylos nor 

 propodos." I am now far from thinking this a correct 

 interpretation of the phenomena. In the second maxillipeds 

 (first gnathopoda) the short strongly spined terminal joint no 

 doubt represents the true seventh. It may be difficult to 

 determine the boundaries of the basal joints, but the three 

 terminal are marked off by the customary flexure. In like 

 manner in the third maxillipeds it is clear that the 

 geniculation occurs between the fourth and fifth joints, and in 

 all probability the sixth joint which is much longer than the 

 fifth represents a coalescence of the sixth and seventh joints. 

 It must, however, be remarked that in Sclerocrango7i Sars has 

 discovered a minute terminal joint, as Kroyer had earlier 

 done in his Crangon nanus, and it is therefore possible that in 

 other genera this dwindled representative of the seventh 

 joint may have vanished altogether, leaving the maxillipeds 

 to end with the sixth. The geniculation referred to is, at any 

 rate sometimes, very pronounced in ^geon, and, inde- 

 pendently of it, Bate's description of the third maxillipeds in 

 his own genus Ponfocaris agrees with the view here set forth 

 and is inconsistent with his definition of the family. 



It happens that Dr. Ortmann makes no mention of 

 Pontocaris, and that Bate takes no notice of u^geon. But 

 specimens from the Cape so minutely agree with Heller's 

 tolerably full description of y^geon cataphractus (Olivi), and 

 at the same time differ so little from Bate's two species of 

 Pontocarts, that I feel no hesitation in making that genus a 

 synonym of y^gcon. 



The genus Rhynchocmetes, Milne-Edwards, included among 

 the Crangonidae in my History of Crustacea, should be 

 removed, since it has an articulated rostrum and a palp to the 

 mandibles. Dr. Ortmaan has established a family Rhyn- 

 chocinetidae. The genus Ntka, Risso, included in the 

 Crangonidae by Sars, should be called Processa, Leach, and 

 referred to the family Processidae, Ortmann, 1896. 



Cheraphtlus, Kinahan, 1862, at its institution not only 

 included the type species oi Pontophilus, Leach, 181 7, but was 



