192 DR. W. T. CALSIAX OX THE MACRUROUS [Mar. 6, 



is " slightly excavated distally on the inner side." While this is 

 quite correct and holds good also for the new species described 

 below, it should be pointed oiit that this very slight excavation, 

 not visible from the outei" side, is very diffei'ent from the mai'ked 

 excavation of the anterioi* mai'gin of the carpus found in most of 

 the species, at least, of the allied genera. Since, however, the 

 excavation is about equally slight in some of the species of 

 Caridina, it does not seem advisable to include this chaiacter in 

 the generic definition. In all cases the terminal brushes of setaj 

 on the fingers of the chelse are more scant}' than in any species 

 of Caridina which I have seen. 



/!(??/ to the S'pecies q/Limnocaridina. 



A. Fingers of chehe five to seven times as long as the 



palm, with very long marginal seta;. 



a. Rostrum about equal to antennular peduncle i. retiarhts, ii. sp. 



b. Rostrum less than half as long as tirst segment of 



antennular peduncle X. pavvula, n. sp. 



B. Fingers of chela; not more tlian twice as long as the 



palm ; setie not very long, confined to distal part. 



a. Length of sixth abdominal somite more than twice 



its depth. 

 a. Rostrum mi\ch longer than the carapace, with 



10-20 teeth below L. tanganyika Caiman. 



h. Rostrum about equal to carapace, with 3-6 teeth 



below T-i. similis, n. sp. 



c. Rostrum less thau one-third of length of carapace, 



unarmed below L. latipes, n. sp. 



b. Length of sixth abdominal somite little more than 



one and a half times its depth. 

 a. Rostiiim nearly equal to carapace; merus of last 



three legs with one spine i. socius, n. sp. 



h. Rostrum little more than half length of carapace ; 



merus of last three legs with 2-3 spines L. spinipes, n. sp. 



LiMNOCARIDINA RETIARIUS, n. sp. (Plate XI. figs. 2-8.) 



Description. — Body slender ; sixth somite of abdomen a little 

 shorter than the carapace, length more than two and a half times 

 its depth. Kostrum (Plate XI. fig. 2) about equal to or a 

 little shorter than antennular peduncle, two-thirds as long as 

 carapace, decurved at base, then horizontal or slightly recurved 

 towards tip, teeth ^^^g"-, unarmed above for nearly half its 

 length fi-om tip. 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 XL fig. 3) 

 projecting beyond external tooth. Third maxilliped extending 

 to end of second segment of antennular peduncle, exopod not 

 longer than i.schium, terminal segment slender but a little shorter 

 than preceding segment. First pera?opods (Plate XI. fig. 4) 

 reaching to tip of third maxillipeds, breadth of carpus two-thirds 

 of its length, chela about three times as long as carpus, palmar 

 portion less than one-fifth of length of fingers. Second ]3era?opods 

 (Plate XI. fig. 5) reaching a little beyond first, breadth of carpus 

 little more than two-fifths of its length ; chela a little more 



