BRAXCHIURA FROM LAKE TANGANYIKA. 275* 



Immediately behind the insertion of the antennule is situated a 

 stout and moderately sharp accessory spine. Eyes rather lai'ge, 

 a little more than one- quarter breadth of carapace apart. 

 Suckers, in the males, rather small, •12--14 of breadth of cara- 

 pace ; in the females, rather large, 'li-'lS of breadth of carapace. 

 Maxillipeds strong and moderately well armed ; basal segment 

 produced into three broad rounded processes; "area" of fair 

 size, pear-shaped, and armed with small spines. A pair of 

 accessory processes, also broad and rounded, is situated between 

 the bases of the maxillipeds, and a second pair, rather slighter, 

 a short distance behind them. Flagella present on the first two 

 pairs of swimming-legs. In the male, vesicula seminalis present 

 on the third leg, copulatory peg and accessory cushion on the 

 fourth. In the female, basal segment of fourth leg produced 

 postero-laterally into pointed lobe. Colour (in formol) light 

 brownish gi'ey, sometimes with a pronounced reddish tinge, the 

 lateral and posterior regions of the carapace lobes showing a 

 distinct radial striation, most clearly seen by transmitted light. 

 Testes covered above by irregular blotches of brown pigment. 

 Dimensions as follows : — 



Adult male (largest specimen). Adult female (largest specimen), 



mm. mm. 



Total length 10-2 Total length ll'l 



Length of carapace ... 6' 7 Length of carapace ... 7*5 



Breadth of carapace... 6*1 Breadth of carapace... 6" 5 



Remarks. — It is not iinusual among the Argulidse for the 

 posterior carapace lobes to exhibit some striation, which is due, 

 no doubt, to the branching of what Wilson calls the side-pouches 

 of the stomach. This appearance is, however, so outstanding a 

 feature of these specimens, that striatus at once suggested itself 

 as a suitable specific name. From the large number of specimens 

 contained in the collection, this would seem to be the commonest, 

 and perhaps the most widely distributed of the Tanganyika 

 species. There are a few small individuals the sexual characters 

 of which ai-e less obvious, and yet others which must be classed 

 as larval forms and do not show the secondary genital modifications 

 typical of the adult. 



Occurrence. — Mbete, 25/9/04. From gill-arches and I'oof of 

 mouth of large male specimen of Dinopterus cuimingtoni (length 

 1020 mm.). Twenty -two males and twenty -five females. 



Sumbu, 13/10/04. From gill-arches and roof of mouth of 

 large Clarias rohecchii. One female, associated with specimens 

 of A. africanus. 



Vua, 29/10/04. From surface of head and mouth of very large 

 female specimen (length 1550 mm., weight 30"6 kilogr.) of a 

 Siluroid (? Clarias lazera) — native name Muomi. A single male, 

 associated with specimens of A. africanus. 



Kasawa, 1/11/04. From mouth and gill-bars of large Z>mo- 

 topteri's cunningioni. Three male and two female specimens. 



