Contributions to the Crustacean Fauna of South Africa. 411 



The South African representatives of this genus can be divided 

 into three groups, characterized as follows : 



Seventh peraeon segment without pro- \ 



rninent processes, one or more of the D. scabncula (Heller), 

 peraeon segments tuberculate, telsonic r D. austmUs, Eichardson. 

 notch widening anteriorly but with- D. bicolor, n. sp. 

 out median lobe. 



Seventh peraeon segment with 2 pro- 

 minent processes, telsonic notch , 



. n YD. (hoxus, n. sp. 



widening anteriorly, with median 



lobe. 



I D. kraussi, n. sp. 



.reraeon segments all smooth, telsonic I ~ , 7 /r ^ \ 



J D. macrocephala (Krauss). 



notch not widening anteriorly. 



(D. ovalis, n. sp. 



D. scabricula and D. dioxus both occupy rather isolated positions, 

 the first on account of its mandibles and uropods, the second in 

 possessing well-developed processes on the 7th peraeon segment. 



DYNAMENELLA SCABRICULA (Heller). 

 (Plate XXXV. A.) 



1866. Spliacroma scabricula, Heller, " Novara " Crust, p. 141, pi. 12, 

 fig. 11. 



As mentioned above under Spliaeramenc polijtijlotus, the specimens 

 assigned by Hansen in 1905 to Heller's species were in reality not 

 that species ; the Spliaeroma (?) scabriculum of Hansen therefore 

 drops out of the synonymy of D. scabricnla (Heller). 



The transverse rows of tubercles on the peraeon segments, which 

 are single in the centre, break up laterally into a number of small 

 tubercles on each segment. 



The two median tubercles on the 7th peraeon segment in the 3 

 are much larger than the rest, in consequence of which the posterior 

 margin is slightly bilobed. 



The 1st pleon segment is narrow, only visible laterally ; the 2nd 

 segment has the pleuron produced forward as an acute process under- 

 riding the epimeron of 7th peraeon segment ; 3rd and 4th segments 

 also narrow. 



There are two small and obscure submedian tubercles on the 4th 

 pleon segment, and 2 submedian rather elongate tubercles at the base 



