BKANCHIURA FROM LAKE TANGANYIKA. 273 



Colour (in spirit) a reddish brown ; in one specimen, the testes 

 are covered by irregular blotches of a darker colour. 

 Dimensions as follows : — 



Adult male (largest specimen). 



mm. 



Total length 2-7 



Length of carapace 2'1 



Breadth of carapace 1'6 



Eemarks. — This species is unfortunately only represented by 

 two specimens, both of the male sex. They appear to be adult, 

 however, although they are small, and there seems no reasonable 

 doubt but that they represent a distinct species. The compound 

 eyes are unusually large, and are actually larger in pi-oportion than 

 in the species which has been named A. megalops. The swimming- 

 legs in these specimens are so backwardly directed, that the bases 

 of at least the last pair are, strictly speaking, covered by the 

 abdomen and not by the cai^apace lobes. 



Occurrence. — Mpala, 31/12/04. From surface of body of small 

 Shnochromis diagramyna. One male specimen. 



Mpala, 31/12/04. From outside body of medium-sized Haplo- 

 chilus tanganicanus. One male. 



Argulus angusticeps, sp. n. (PI. XLII. figs. 10, 11 ; PI. XLIV. 

 figs. 26, 27.) 



Description. — Carapace (in the female) elliptical, considerably 

 longer than broad, with antero-lateral depi^essions well marked. 

 Posterior lobes moderately broad, rounded, covering bases of all 

 but fourth swimming-legs, and separated by a somewhat narrow 

 sinus, more than one-third the length of the carapace. The edge 

 of the carapace below is well armed with very small spines which 

 barely extend to the region of the swimming-legs. Abdomen in 

 the female slightly longer than broad, about one-quarter entire 

 length of body; posterior lobes somewhat pointed but with 

 rounded tips, and separated by moderately broad sinus one-half 

 length of abdomen. The f ureal appendages, which are very small 

 and inconspicuous, lie at the bottom of the anal sinus. Antennules 

 and antennfe small, but moderately armed, approaching closely to 

 one another in the mid line. Basal segment of the antennule 

 with posterior spine ; second segment with stout anterior spine, 

 posterior blunt spiniform process, and slender lateral hook. 

 Antennae with slight spiniform projection on basal segment. 

 Immediately behind the insertion of the antennule is situated 

 a stout accessory spine. Eyes large, one-sixth breadth of carapace 

 apart, and far forward. Suckers small, -11 of breadth of carapace. 

 Maxillipeds strong and well armed ; basal segment produced 

 into thi^ee stout and sharp spines; "area" of fair size, roughly 

 oval, and armed with small spines. Both suckers and maxillipeds 

 are situated unusually far forward. A pair of stout accessory 

 spines is situated between the bases of the maxillipeds, and a 



