The Echinoderm Fauna of South Africa. '>>> 



* OPHIODERMA WAHLBERGII. 

 Miiller and Troschel, 1842. Sys. Ast., p. 87. 



This species, describe*] originally from Port Natal, has not been 

 met with since, nor has it ever been figured. Bell (1905, Mar. Inv. 

 South Afr., vol. 3, p. 255) says it "appears to be widely distri- 

 buted as there are examples in the Museum from the Red Sea and 

 from Puerto Cabello." The occurrence of an Ophioderma in the 

 Red Sea, whether identical with one from Natal or not, would seem 

 to be worthy of more than this scant, passing notice, and surely \ve 

 might have been informed a little more particularly as to the grounds 

 on which specimens from Venezuela, the Red Sea and Natal are 

 regarded as identical. It is certainly a unique distribution. Accord- 

 ing to Miiller and Troschel, the Natal species is very well character- 

 ized, and it is much to my regret that I find no specimens in the 

 PIETER FAURE collection. 



OPHIOLEPIDIDAE. 



This large, cosmopolitan family is well represented in South 

 African waters, by a small but diversilied group of species, belong- 

 ing to seven genera, three of which are of worldwide distribution, 

 one is a distinctly Indo-Paciiic littoral group, and the others are 

 deep water genera of whose actual range our knowledge is still 

 incomplete. Only one of the species here included is new to science, 

 but the occurrence of two specimens of the extraordinary genus 

 Astrophiura is of no less interest, though the genus had already 

 been reported from the Agulhas Bank. The following key shows 

 the diagnostic characters of the eleven species here listed. 



Key to the South African Species of Ophiolepididae. 



Side arm-plates of one or more basal arm -segments greatly extended laterally so 

 as to meet corresponding plates of adjoining arms, or prevented from that only 

 by the genital plates. 



Basal arm-segments with their side-plates in contact all around the true disk 

 area ........ Astrophiura cavellae. 



Basal segments of adjoining arms separated by genital plates 



Ophiomisidium pulchelhim. 

 Side arm-plates of basal arm-segmeuts not extraordinarily widened. 



Tentacle-scales on second oral and first arm-pores numerous (5 15). 



Radial shields at margin of disk, in contact with basal upper arm-plates ; 

 upper ends of genital plates not extending above dorsal surface of arms. 

 Arm-spines minute, peg-like. 



