1906.] CRUSTACEA OF THE THIRD TANGANYIKA EXPEDITION. 195 



Kituta Bay, 27.viii.04. "Tow-netting, surface, 8.30 p.m." 

 Two specimens. 



Mbete, 1.X.04. " Taken shore- wading." One female. 

 Kasawa, 7.X.04. " Tow-netting, 8.30 p.m." Many specimens. 

 Kalambo, 4.xi.04. " Tow-netting, 8.20 p.m." Three specimens. 

 Kazagga, 7.iii.05. " Taken close to shore." One specimen. 



LiMNOCAEiDiNA siMiLis, sp. n. (Plate XII. figs. 15-22.) 



Description. — Body slender ; sixth somite of abdomen shorter 

 than the carapace, its length about two and a half times its 

 depth. Rostrum (Plate XII. fig. 15) a little longer than 

 antennular peduncle, equal to or shorter than carapace, slightly 

 arched at base, then horizontal, teeth — g~-, unarmed above for 

 half its length. Antero-lateral spine of carapace set well back 

 from front edge. Antennular peduncle reaching to external 

 tooth of antennal scale. Distal edge of scale (Plate XII. fig. 16) 

 projecting well beyond external tooth. Third maxilliped not 

 reaching to end of second segment of antennular peduncle, 

 terminal segment little shorter than preceding. First perteopods 

 (Plate XII. fig. 17) short and stout, reaching to about the first 

 third of first segment of antennular peduncle, breadth of carpus 

 about three-fifths of its length, chela more than one and a half 

 times as long as the carpus, tw'ice as long as broad, fingers equal 

 to the palmar portion. Second perasopods (Plate XII. fig. 18) 

 reaching a little beyond first pair, breadth of carpus about one- 

 third of its length ; chela little longer than carpus, three times as 

 long as broad, palmar portion two-thirds of length of fingers. 

 Third pereeopods extending beyond and fifth pair falling con- 

 siderably short of tip of third maxillipeds ; dactylus of last three 

 pairs more than one-third of propodus, that of third and fourth 

 (Plate XII. fig. 19) with 14-15, that of the fifth (Plate XII. 

 fig. 20) with 21 spines. Telson (Plate XII. fig. 22) four-fifths of 

 length of sixth abdominal somite. Outer plate of uropods longer 

 than inner. 



Total length, $ , 16-5 mm. Eggs -28 x -18 mm. 



Remarks. — This species is closely allied to L. tanganyikce, but 

 is distinguished by the much shorter rostrum. One very remark- 

 able feature is the strongly marked difference between the sexes 

 in the armature of the third and fourth perseopods. In the 

 male (Plate XII. fig. 21) the marginal spines on these segments 

 greatly exceed in size those of the female. A similar difference, 

 though less strongly marked, is found in the species described 

 below as L. sociits, but in the other species of the genus I have 

 not been able to perceive any difference between the sexes in this 

 respect. 



Occurrence. — -Kalambo, 4.xi.04. " Tow-netting, 8.20 p.m " 

 One specimen. 



Rusisi River, close to Tanganyika, 7.iii.05. Many specimens, 

 mostly females. 



Proc. Zool. See— 1906, Yol. I. No. XIV. 14 



