212 



the outer lobes are short, oval, and distally terminate in two papillae, each 

 bearing a pair of short setae; the inner lobes are 1/4 the length of the 

 outer and bear two setae on the straightly truncated distal margin. 



The pereopods are long and thin. In pereopods I the 2nd segment 

 is broader than the rest; the 5th segment is 1.5 times longer than the 

 6th; the posterior distal angle of the 6th segment extends over the claw 

 and terminates in a strong seta; the claw is almost half the length of the 

 6th segment and is slightly curved. Pereopods II ai^e somewhat shorter 

 and weaker than pereopods I; the 6th segment is equal to the 5th and 

 does not have a process above the claw; the claw is long and straight. 

 Pereopods III and IV are exceptionally thin; the 4th, 5th and 6th segments 

 are mutually almost equal, the latter two are arcuately curved; the claw 

 is medium in length and straight. The 2nd segment of pereopods V has 

 a smooth anterior and finely denticulate posterior margin; the process 

 on the anterior distal angle is very short and several times into the 3rd 

 segment; the length ratios of the 2nd, 4th, 5th, and 6th segments are 

 12:10:5:4.5. The length ratios of pereopods VI are somewhat different; 

 the 6th segment is the next largest after the 2nd; the length ratios of the 

 2nd, 4th, 5th, and 6th segments are 16.5:10:9:13. In pereopods VII the 

 5th and 6th segments are equal in length and both insignificantly shorter 

 than the 4th segment; the claw is very small. 



The urosomites are stretched; II and III together are longer than I. 

 The basipodites of the uropods are longer than the rami. The margins 

 of uropods I are smooth, in uropods II the distal part of the posterior 

 177 margin is denticulate. In uropods III the inner margin of the exopodite is 

 finely denticulate. The telson is stretched and triangular, its length twice 

 its basal width. 



Notes: The species described below — 5. pusilla and S. typhlops — are 

 fairly close to S. latifrons and together form an Natural group. S. chelata 

 is close to this group in some features. 



Distribution: A rare species, known from a few specimens from the 

 tropical parts of the Atlantic Ocean, from the western part of the Indian 

 Ocean (south of Socotra Island), and the Hawaiian Islands. 



This species is absent in our collections. 



27. Scina pusilla Chevreux, 1919 (Fig. 88) 



Chevreux, 1919: 5; Wagler, 1926: 404; Vinogradov, 1960a: 234, 

 1962: 17, 1970: 394. 



Length of sexually mature specimens 3.0-4.0 mm. 



In external appearance it is very similar to S. latifrons. The pereon 

 is very broad dorsally and tapers sharply after somite V. Antennae I are 

 very wide and in length insignificantly shorter than the pereon. Keels are 

 absent on the body and very weakly developed on the head, so much so 

 that sometimes they are not distinguishable. The mouth cone is small. 



