ON BOSMINTDJE, MACBOTHRICID^:, ETC. 869 



XI, PI. XI, figs. 6-9 ; and Trans. Tyneside Fat. Field 

 Club, Yol. VI, p. 55. PI. VI, figs. 6-9. 

 Ilyocryptus sordidus, G. 0. Sars. Om de i Omegnen af Christia- 

 nia forekommende Cladocerer (1861), p. 12; and Andet 

 Bidrag. (1862), p. 34. 



At the conclusion of the description of this species in a former 

 paper, published in the Trans. Tyneside Xat. Field Club, the Bev. 

 A. M. [Norman remarked — " We have already referred to the fact 

 that this species does not appear to embrace all the characters 

 which are assigned to the genus Accmtholeleris. It agrees with 

 A. curvirostris in the number of setae attached to the posterior 

 antennae, and also in the presence of setae of great length at the 

 posterior ventral angle of the carapace. It differs in the fact, 

 that the setae of the first two joints of the lower branch of the 

 posterior antennae are short, and do not differ in character from 

 the ordinary plumose setae of the Daphniadae. But a more im- 

 portant divergence would appear to exist in the structure of the 

 intestinal canal, which does seem to possess a loop near the excre- 

 tory orifice as in A. curvirostris ; nevertheless, a great dilatation 

 of the canal exists in an analagous position, forming apparently a 

 strong muscular rectum. At the same time we speak with hesi- 

 tation, and our opportunities of investigating the structure of the 

 species have not been sufficient to enable us to speak with cer- 

 tainty on this and other points." G. 0. Sars having now estab- 

 lished a genus for its reception that genus is here adopted ; Sars 

 has also found a second species in the Swedish lakes, which should 

 be sought for in our Islands. 



To the two localities in the neighbourhood of Sedgefield, where 

 /. sordidus first occurred in Britain, and was noticed by Mr. 

 Norman, Mr. Brady has now added a third, viz., the Eastern 

 Lake at Belsay, Northumberland. Fischer has found the species 

 near Moscow ; Leydig and Lievin in Germany ; and G. 0. Sars 

 in Sweden. 



Family. LYNCEIM1. 



Shell of the head greatly produced on each side, shield-shaped, 

 and extending downwards to form a well marked rostrum, which 



