Marine biological station at port erin. 19 



the carapace, obliquely truncate ; almost horizontal ; 

 lower margin with two or three teeth near the extremity 

 and two or three near the base. 



Fourth pair of legs with an exopodite or imperfect 

 natatory appendage, two-jointed, reaching nearly to the 

 end of the first joint, which is almost as long as the 

 remaining four. 



Telson triangular, as in Leucon. 



Uropoda with peduncle and both rami subequal in 

 length ; peduncle almost spineless, inner ramus with six 

 unequal spines on the inner and two on the outer side of 

 the first joint ; second joint with two very short and 

 slender spines on the inside ; outer ramus obliquely 

 truncate, with five plumose setae on the inner side and 

 four at the end. Length 5j mm. 



Male : — Upper margin of carapace as long as the free 

 segments ; lower margin with five or six teeth on the 

 anterior half increasing in size anteriorly, forming a right 

 angle with the anterior margin which has five teeth just 

 below the rostrum, the second from the rostrum being 

 the largest ; rostrum horizontal, blunt, about one-sixth 

 the length of the carapace, with five small teeth on the 

 lower margin. 



First pair of legs with seven teeth on the lower margin 

 of the first joint. Second pair with a large spine at the 

 distal end of the second, and two unequally long spines 

 at the end of the third joint. Third pair with an append- 

 age on the second joint, consisting of two parallel curved 

 blades, twice as long as the succeeding three joints. 

 Length 8J mm. 



The above interesting species has a general resemblance 

 to Leucon, from which genus, however, it may be at once 

 distinguished by the appendages on the fourth pair of 

 legs in the female and the third pair in the male. It was 



