REPORT ON THE ISOPODA. 11 



Tlie antennae are unfortunately broken off at the fourth joint ; the three proximal 

 joints are very short, the third being the longest; this latter bears on the outer side an 

 articulated scale (figs. 3 and 5), which appears to me in all probability to have the signifi- 

 cance of an exopodite. The shape of this scale is rather peculiar ; it is suboval and folded 

 in the middle line, the margins are beset here and there with long delicate hairs, and the 

 whole structure has thus very much the appearance of a leaf of Dionsea muscipula. 



The mandible has the apex divided into two principal lobes and then again into a 

 number of tooth-like processes ; beneath is a closely set tuft of peculiar serrate spines, 

 at right angles to the longer axis of the mandible and parallel to the molar process, which 

 is strong and well developed. The palp is long and three-jointed ; the distal joint is 

 oval and flattened and furnished along one edge with a closely set row of rigid hairs, 

 which do not extend quite as far as the articulation of this joint with the preceding ; the 

 middle joint is long and stouter at its basal portion, distally it is furnished with a row of 

 hairs like those upon the third joint, and also with two strong spines serrate along one 

 margin. 



The maxillss of the first pair consist as usual of two pieces, the upper being the longer 

 and stouter of the two ; both are furnished along the cutting edge with numerous slender 

 hairs and stoutish spines ; some of these latter are serrate on the upper lobe of the 

 maxilla. 



The second pair of maxillae I have not seen. 



The maxillipedes are not in any way remarkable in their structure ; the inner 

 margin of the stipes is provided for a small portion of its extent with a series of round 

 bodies articulated by a narrow stalk, in which no structure could be discerned ; they no 

 doubt correspond to the sensory (?) organs having a similar location on the maxilli- 

 pedes of many Munnopsidae ; the upper extremity of the stipes is truncated and beset 

 with short stiff hairs ; the palp is five-jointed, and does not project much beyond 

 the end of the stipes ; its joints are fringed along the inner margin with long hairs ; 

 the first three joints are broad, the two distal joints muchnarrower. 



TIiq Jirst pair of ambulatory limbs are extraordinarily long and are modified to form 

 a prehensile hand, the length of the limb, which is figured on PI. IV. fig. 4, is not much 

 less than that of the body itself. The proximal joint is long and narrow ; the three 

 following joints grow shorter, and at the same time wider, towards the extremity of the 

 limb ; the outer side of each is prolonged considerably beyond the articulation of the 

 succeeding joint ; these joints are abundantly furnished with long slender unbranched 

 hairs ; the penultimate joint is greatly swollen and three-sided, the inner and outer 

 margins are convex and beset like the preceding joints with fine slender hairs ; the third 

 side is almost straight ; at its junction with the inner margin of the limb is a single stout 

 spine ; and along the edge is a row of serrate spines, below which are a few fine slender 

 hairs. The distal joint of the limb is short and curved, and of about the same length as 



