The Echinoderm Fauna of South Africa. 299 



of this species are sent from False Bay, '20-30 fms". Besides these 

 two, there are nine other Pterasters from half a dozen stations which 

 seem to be identical with them. As this is evidently the common 

 pterasterid of South Africa, I should have no question about consid- 

 ering it Gray's species (it answers his brief description satisfactorily) 

 were it not that Perrier, who had seen Gray's specimen, says that 

 capensis and cribrosus agree in having "un reseau a large mailles 

 formees de ligaments unissant les epines," etc. The specimens at 

 hand differ from cribrosus strikingly in the absence of such a reticulum, 

 except in the outer part of the actinal interradial areas. Either 

 Perrier was mistaken, or capensis is very variable in the extent to 

 which the meshwork is developed, or the specimens before me are 

 not capensis. 



It is an interesting and surprising fact that these South African 

 Pterasters which I am here calling capensis, can be distinguished only 

 with great difficulty from specimens of the same size, of Pteraster 

 tessellatus Ives from Puget Sound ! In fact after careful comparison, 

 the only constant difference seems to be in the structure of the 

 paxillae: in capensis each paxilla has a single central spinelet of a 

 size about equal to the surrounding series of 6 or 7 similar spinelets, 

 while in tessellatus instead of this central spinelet is a cluster of 

 smaller and more slender spinelets. This difterence is not conspicuous 

 but it seems to be constant and is certainly important. 



Some specimens of capensis, and of tessellatus also, have a well 

 marked reticulum along the lower sides of the rays. It is possible, 

 though I have no evidence to support the view, that there is much 

 variation in the extent of this reticulum and the British Museum 

 type may possibly have it developed dorsally. But if this proves to 

 be so, it will be useless to try and maintain Metasler as a separate 

 genus. 



The specimens before me range from R = 53 and r = 40 mm. 

 (R = 1-325 r), to R == 19 and r = 12 (R = 1-6 r). One specimen has 

 R = 36 and r = 20 (R = l'8r) which is the extreme arm-length for 

 the group in which capensis and tessellatus belong. 



P.F. 2336. Lions Head, Cape Town, N. 67 E., 25 miles. 131-136 fms. 

 Blk. spks. 1 specimen; small adult. 



P.F. 2429. Lions Head N. 84 E., 38 miles. 195-204 fms. Blk. 

 spks. 2 specimens; small adults. 



P.F. 14532. Cape Point N. 50 E., 18 miles. 180 fms. Gn. s., 

 blk. spks. 2 specimens; young. 



P.F. 18154. Cape Point N.E. by E. 3 / 4 E., 18 miles. 200 fms. 

 Fne. s. 1 specimen; young. 



