34 DE. W. T. CALMAN ON NEW OR EAEE 



Exopod nearly twice as long as the peduncle, roughened on its outer surface with 

 irregular tubercles or blunt teeth, with two unequal spines at the tip and a single seta 

 on the inner edge. Endopod only a little shorter than the exopod ; first segment twice 

 as long as the second, the latter with a long stout terminal spine and a smaller one 

 internal to it, inner edge unarmed. 



Bemarks. — This species differs from the two species of the genus already known in 

 having the pseudorostrum produced vertically and in possessing a lateral longitudinal 

 ridge on the carapace. In the large size of the pseudorostrum it approaches the genus 

 Pseudoleucon of Zimmer, and suggests that that genus should not be separated from 

 EudoreUopsis. 



Occurrence. — " Lyttleton Harbour." 1 specimen. Copenhagen Museum. 



Genus Heteeoleucon, gen. nov. 



Only the first and second pairs of legs have exopods in either sex. The endopod of 

 the uropods is unsegmented. The male has no pleopods. 



Type species //. akaro'ensis, sp. n. 



The general form of the body is that of the genus Leucon, the carapace having a 

 prominent pseudorostrum and a serrated dorsal crest (in the female). The very 

 oblique pseudorostrum recalls the genus Pseudoleucon of Zimmer, from which, how- 

 ever, the present form is distinguished by the fact that the peduncle of the antennules 

 is not sharply geniculate between the first and second segments. 



Heteroleucon AK.uiOENSis. sp. n. (Plate VIII. figs. 11-23.) 



Description of adult Female. — Total length 2*75 mm. 



Carapace a little less than one-fourth of total length, compressed, its vertical height 

 about two-thirds of its length. The dorsal edge is slightly arched as seen from the 

 side, keeled, serrated in its anterior half with eight to ten teeth, and with a single 

 larger tooth just in front of the posterior margin. In front of the posterior tooth 

 there is generally a shallow rounded excavation of the dorsal edge, but in some cases 

 this is less marked than in the specimen figured. The pseudorostrum is straight, 

 directed obliquely upwards, and sharply pointed. The length of its upper edge is a 

 little less than one-third of the length of the carapace. The antennal notch forms a, 

 rather shallow rounded sinus in the antero-lateral margin, which has one or two teeth 

 above the notch and below it is coarsely serrated and curves backwards into the lower 

 margin without any distinct antero-lateral angle. 



The abdomen is rather stout and is a little shorter than the cephalothoracic region. 



The antennules have the first two segments of the peduncle very stout and subequah 

 the third only half the diameter of the second and two-thirds of its length. The 



