54 



a brownish red flush. The specimens in formalin sent me 

 from the Cape correspond well with the colour description of 

 Idotea af/i/u's given by Krauss and Heller, the general effect 

 being a dark appearance dorsally. 



As the species has been carefully and accurately described 

 by Mr. Miers, it is unnecessary to repeat what can be found 

 in his important work on the Idoteidae. It may, however, 

 be mentioned that the eyes are irregularly round and some- 

 what prominent, and that there is a rather conspicuous spine 

 on the inner margin of the penultimate (sixthi joint of the 

 peraeopods a little above the middle. In the large dredged 

 specimens the fourth, fifth, and sixth joints of both gnathopods 

 and first four peraeopods are thickly coated with hair on the 

 inner margin, while in the longer fifth peraeopods the fifth and 

 sixth joints are almost smooth, but in the smaller beach 

 specimens sent me all the peraeopods have the joints in 

 question comparatively smooth, and thus show the marginal 

 spine of the sixth joint much more distinctly than is the case 

 in the larger specimens. 



No description appears to have been given of the mouth- 

 organs of this species, but IVIilne-Edwards has supplied a 

 figure of one of the mandibles and of the maxillipeds. The 

 epistome, or that part of it distinguished by DoUfus as the 

 mesepistome, has the usual conical prominence above or 

 forward, and is produced below or backward so as to flank on 

 either side the transversely oval labrum or upper lip. The two 

 lobes of the lower lip are roughly rotundo-quadrate, con- 

 verging below. The left mandible has a straight trunk, the 

 cutting plate horny in appearance, divided into three or four 

 broad teeth, the secondary plate having three strong teeth, 

 the spine-row about five slender serrate spines ; the molar is 

 strong and prominent, with an accessory brush of setae ; 

 above the molar there is a process, near the point at which 

 the palp might be expected, were it present. The right 

 mandible has the trunk geniculate, the teeth of the cutting- 

 plate more tooth-like, the secondary plate with about four 

 slender teeth ; there is also a marginal tuft of hairs to the 

 rear of the molar, but these may be present though not 

 observed, also on the other mandible. The first maxillae 

 have six strongly plumose setae on the narrow inner plate 

 and ten stout apical spines on the outer. The three plates of 

 the second maxillae are approximately equal in breadth. In 

 the maxillipeds the epipod is slightly narrowed distally, with 

 a rounded apex turned in upon the first joint of the palp ; the 

 narrowly oblong plate which surmounts the long second joint 

 of the stem has on and near the apex several spines and 

 plumose spiniform setae, and also on the inner margin near 



