22 DE. W. T. CALMAIS ON NEW OE EAEE 



EocuMA LATA, sp. n. (Plate VI. figs. 7-12.) 



Description of immature Female. — Total length 3-9 mm. 



The carapace is less than two-sevenths of the total length, very broad and fl.attened, 

 with vi'ell-marked lateral carinse. The greatest vpidth, across the lateral cornua a little 

 behind the anterior third, is very little less than the length. The lateral cornua 

 are short, with acute tips directed forwards. The postero-lateral edges are nearly 

 straight. The width of the posterior margin is less than half that measured across the 

 cornua. The pseudorostrum is prominent, and formed, as seen from above, of two 

 rounded lobes. External to these on each side the antero-lateral margin forms an 

 obtusely triangular tooth with an acute spiniform point, turned forwards, not reaching 

 so far as the level of the pseudorostral lobes. Between this antero-lateral tooth and 

 the lateral cornu the margin is nearly straight. The dorsal surface is slightly arched 

 and has no distinct median keel, but a pair of well-marked dorso-lateral keels running 

 from about the posterior ends of the frontal suture to the hind margin. On the under- 

 side a transverse ridge runs from a little behind the lateral coruu to the free margin of 

 the carapace. The ocular lobe is not broader than long and the pseudorostral plates 

 meet in front of it for a distance greater than its length. The eye is not pigmented 

 and no corneal facets were observed. 



The surface of the carapace is beset with shallow pits which interrupt as clear spots 

 the minute reticulate texture of the exoskeleton. The centre of each pit is occupied 

 by a minute granule (or perhaps a pore). 



The slender abdomen is longer by more than one-fourth than the cephalothoracic 

 region. The fifth somite is about three and a half times as long as broad. The last 

 somite is depressed and expanded laterally, being, at its posterior end, one and a half 

 times as broad as the preceding somite. The antennules have the first segment of the 

 peduncle longer than the other two together, the third not quite half as long again as 

 the second and less than three times as long as broad. 



The distal segments of the first legs are together about one and three-quarters 

 as long as the basis. The carpus is equal to the propodus and nearly one-third longer 

 than the dactylus. 



The uropods are about two-thirds longer than the last somite. The peduncle is a 

 little more than one-third of the length of the subequal rami. There is a plumose 

 seta on the inner edge of the peduncle and another, along with three spinules, on the 

 inner edge of the endopod. 



Eemarhs. — The specimens here described are very immature as compared with the 

 sub-adult specimens of E. taprolanica formerly described. This is shown especially by 

 the characters of the branchial apparatus, which has only about eleven lobules, becoming 

 very small posteriorly, and probably also by the fact that there is no spine on the ischium 

 of the second legs. Further, the outline of the carapace has a distinct resemblance to 



