524 



s. isi in : 



the foremost being the smallest and the hindmost the largest. The 

 convexity of the plates also increases gradually in the more posteriorly 

 situated ones, the fifth pair being in part so vaulted as to present an 

 almost pouch-like appearance. 



Metasome. The body is abruptly narrowed at the somewhat 

 cylindrical metasome, which thus stands in conspicuous contrast with 

 the massive mesosome. At base rather thick, it gradually tapers 

 distally, finally to terminate with a davate end-piece. The metasome 

 is usually slightly bent towards the left side of body. It is fairly 

 distinctly segmented, showing six segments inclusive of the davate 

 end-piece. 15 Appendages of the metasome or the pleopods are present 

 in only four pairs, the two hindmost segments being devoid of any 

 appendage. The pleopod is attached to the posterior part of the 

 segment it belongs to, and is composed of two ovate or subcircular 

 plates, each with a short stalk and both connected by a short common 

 stalk to the metasome. The size of pleopod is usually larger in 

 anterior than in posterior pairs. All the pleopods seem to be of 

 respiratory nature. Measurements of the metasome taken from specimen 

 A are as follows : 



Length of entire metasome, 3,5 mm. 



Thickness at base, 0,8 mm. 



Length of the two distal segments without appendages taken 

 together, 1,31 mm. 



Pleopod of the ist pair, 





Length including stalk. 



Width. 



One of the plates 

 The other plate 



1,037 mm - 

 0,946 mm. 



0,651 mm. 

 0,688 mm. 



1) Sars states of the genus Athclges in general that the metasome consists apparently 

 of only 5 segments, and that the last 2 segments are united to a narrow, more or less 

 claviform piece, although he figures 6-segmented metasome for Athelges temiicaudis G. O. 

 Sars (loc. cit. pp. 209, 210, and PI. 89). 



