736 I'UuF, G. o. SAKS ox [May 3, 



in five of the samples from Tanganyika, and in some of these 

 it occurretl rather abundantly. The localities are as follows : 

 No. 82, Kituta Bay (S. end of lake), No. 97, Niauikolo 

 (S. end of lake), No.'l38, Sumbu (S.W. of lake). No. 169, Kala 

 (E. shore of lake). No. 240, Baraka (N.W. shore). In the last- 

 named locality it seems to have occurred in great abundance, 

 and a good many of the specimens captured had also been 

 separated from the sample by Dr. Cunnington and placed in a 

 small tube. 



5. Paracypria deflexa, sp. n. (Plate LXVI. figs. 1-6.) 



specific Characters. — Female. Shell moderately compressed; 

 seen laterally (fig. 1) of oval reniform shape, greatest height 

 occurring somewhat behind the middle and slightly exceeding half 

 the length, anterior extremity evenly rounded, postei-ior scarcely 

 narrower and obliquely detlexed, terminating in an obtusely 

 triangular corner, dorsal margin evenly curved with the greatest 

 curvature behind the middle and sloping rather steeply to the 

 deflexed hind corner of the shell, ventral margin very slightly 

 concave in the middle ; seen dorstilly (fig. 2) oblong-ovate in 

 form, with the greatest width exceeding one-third of the length, 

 anterior extremity somewhat narrower than posterior. Valves 

 rather imequal, the right being considerably overlapped by the 

 left both in front and behind, anterior lip of left valve (fig. 4) 

 exhibiting a somewhat thickened zone crossed by numerous grooves, 

 from the bottom of which delicate hairs arise. Surface of shell 

 smooth and shining, though exhibiting a few small dots similar 

 to those found in P. complanata and P. conoklea. Muscular 

 impressions in the centre of each valve (fig. 5) very distinct and 

 arranged as in the other species of this genus. Caudal rami (fig. 6) 

 distinctly curved ; claws moderately strong and only slightly 

 unequal, the distal one exceeding half the length of the ramus ; 

 dorsal seta well developed and rather slender. 



Male (fig. 3) a little smaller than female, but exliibiting a 

 closely similar shnpe of the shell. 



Length of shell 5 ^^''^•'^ ini"-, height 0-40 mm., width (>-2() nun. 



Remarks. — In external appearance this form somewhat resend^les 

 a C'andona, the shell exhil)iting in the lateral aspect a rather 

 similar shape and having the hinil corner deflexed in a similar 

 manner to that found in the more typical species of that genus. 

 It is, however, a true Paracypria, as ])roved by the examination 

 of the several appendages, which agree closely in structure with 

 those in P. ohiusa. 



Occurrence. — Of this species also a. considerable number of 

 specimens ha.s been secured. I have noted it in four of the 

 Tanganyika samples. In two of these samples (138 and 240) it 

 occuried rather plentifully in company with P. ohtvsa. In the 

 other two (97 and 169) only solitary specimens were found. The 

 localities from which the samples woie taken have been recorded 

 above. 



