67 



ExOSi'IlAERo^lA \\1.1DUM, 11- S])- 

 Pj.ATE I 2 A. 



The head of this species is (Ustinguished from that of E. ampli- 

 f rolls chiefiy by the want of any eccentric elevation above the 

 eyes, its upper Hne in a front view being gently convex instead of 

 forming- an almost pointed arch. 



The pereeon is broad, with the imbrication even more strongly 

 marked than in E. ainplifrous, the transverse ridges occasionally 

 carrying four widely spaced low lubercles, which, however, were 

 obsolete in the specimen figured. Theintegumem . wiatall 

 eroded- The segmentation of the pleon is as in the preceding 

 species, but here the basal part has two tubercles instead of great 

 bosses, and the terminal part, though it carries two large bosses 

 surmounted by two tubercles, ends in a commonplace manner, 

 the apical margin being truncate and shallowly trifid like the 

 British form known as Sphaeroma prideauxianum. 



The first and second antennae are distinguished from those of 

 £. ampUfrons by characters of doubtfully specific value- In the 

 first pair the first joint is more massive, but the angular projec- 

 tion on the side margin is much less prominent. In the second 

 pair the penultimate joint of the peduncle is shorter than the 

 ultimate. That the flagella have a joint or two more than 

 ■observed in the other species cannot be a matter of importan ;e. 



The u ppi T i I p on the inner side has the transver.--' ; i le above 

 the apical margin more prominmt. straighter, and carrying 

 stronger setules than in E. ainplifrotis. 



The mandibles arc less massive than in the species just men- 

 tioned, though generally similar, but Avith the cutting plate more^ 

 outdrawn, the secondary plate on the left mandible trilobed, 

 obscure, and at most very slight on the right ; on both there is a 

 distinct spine-row of five or six spines, some of which are a little 

 denticulate- The molar has on one side above the crown a small 

 r.ppendage, probably common to all the species. The palp is a 

 little stronger than in E- aniplifrons, but as there, with the joints 

 nearly equal, the second and falcate third fringed with spines, of 

 which two or three at the apex of each of these joints are the 

 longest- 



The lower lip and maxillae are as in E. ampUfrons, but the 

 maxillipeds have a rather differently-shaped plate to the second 

 joint, its greatest breadth being at the middle, and the apical 

 margin much more oblicpie. On one of the first maxillae eleven 

 spines could be counted on the outer plate- 

 First gnathopods — These are nearly as in the preceding species, 

 but the fourth joint has a row of seven spines with two others out 

 of the row, the fifth has five spines, and the sixth has six. The 

 other limbs may show similar flifferences, but they are not 

 •striking. 



