326 Annals of the South African Museum. 



Arm-spines 6 8, short . . . Amphiura capensis. 



Arm-spines 4 or 5, longer than arm- segment Amphiura angularis. 

 Tentacle-scales 2. 



Radial shields several times as long as wide, their length ex- 

 ceeding one-half disk-radius 5 upper arm-plates not wider than 

 long ...... Amphiura Candida. 



Radial shields 2 2'5 times as long as wide, not nearly one-half 

 disk-radius; upper arm-plates much wider than long 



Amphiura incana. 

 More than two oral papillae on each side of each jaw. 



Three oral papillae on each side, outermost wide and operculiform, 

 equalling or exceeding the other two together in width. 



Disk scales relatively coarse, especially at center of disk where some 

 are '25 - 30 mm. across; 5 7 series of scales in each interradial 

 area where narrowest; radial shields large . Amphipholis minor. 

 Disk scales much smaller, more numerous ; radial shields smaller, 

 less conspicuous .... Amphipholis squamata. 



Four oral papillae on each side, outermost not greatly enlarged ; tentacle- 

 scales 2 ; arm-spines 3. 



Margin of disk ornamented with round tubercles or papillae 



Amphioplus gibbosus. 

 No papillae or tubercles on disk margin. 



Radial shields short, broadly in contact, equal to about one- 

 third disk-radius ; arms, 4 5 times disk-diameter 



Amphioplus integer. 



Radial shields long, in contact, equal to half disk-radius ; arms 

 more than 7 times disk diameter . . . Amphioplus hastatus. 



Tip of each jaw without oral papillae, but occupied by the lowest tooth. 

 Upper arm-plates broadly oval, twice as wide as long, fully in contact 



Ophiactis carnea. 

 Upper arm-plates more or less triangular little or not at all in contact. 



One oral papilla on each side of jaw, large scale-like Ophiactis plana. 

 Two oral papillae on each side of each jaw . Ophiactis abyssicola. 



AMPHIURA DILATATA. 

 Lyman, 1879. Bull. M. C. Z., vol. 6, p. 26; pi. XI, figs. 314-316. 



There is good reason for believing that this species is identical 

 with Ljungman's atlanticn from St. Helena. The only difference is 

 that dilatata is known to have the lower surface of the disk bare, 

 while one infers from Ljungman's description that such is not the 

 case in atlantica, although nothing is said one way or the other about 

 the matter. If the St. Helena species does have the interbrachial 

 areas below, naked, the identity of the two species would be clear 

 and the' name atlantica would have priority. The CHALLENGER took 

 ditatata only at her station 141, in 98 fms. but the PIETER FAURE 





