290 Annals of the Sauth African Museum. 



tered, calcareous plates, a few of which carry very small spinelets. 

 Abactinal plates with scattered spines, 1-2 mm. long, thick and 

 pointed; these spines do not show any serial arrangement either 

 longitudinal or transverse. Along the sides of the ray, limiting the 

 ventral surface is an indistinct series of inferomarginal plates, each 

 of which carries a single spine about 2 mm. long. Actinal inter- 

 radial areas rather large, traversed by about five series of more or 

 less imbricated plates, between which is thin, naked skin. Madre- 

 porite conspicuous, 2 mm. across. 



Adamulacral plates, each with two spines, of which one, usually 

 much the smaller, is on the somewhat projecting inner margin of 

 the plate, while the other, which may be 2-5 mm. long, is on the 

 actinal surface of the plate ; these spines are either blunt or pointed, 

 are often flattened and are more or less irregular in both size and 

 position. Actinal intermediate plates do not extend half the length 

 of the arm and are usually quite bare ; in no interradial area are 

 there more than half a dozen scatterd spines. Oral plates rather 

 large, very little swollen ; each carries a large, pointed flat spine at 

 its inner end, a larger, blunt spine on the surface posteriorly and 

 about three much smaller, sharp spines, or spinelets, on the free 

 margin. Colour (dried) light yellow-brown, the bare skin darker 

 than the plates. 



P.F. 2798. Vasco de Gama Peak, N. 71 E., 18 miles. 230 fms. 

 Stones. 1 specimen. 



Holotype, South African Museum, no. A 6416. 



This interesting little starfish is very near the type-species of the 

 genus, P. echinaster, from 53 fms. in Nassau Bay, Tierra del Fuego. 

 It differs in the presence of only one spine on each inferomarginal 

 plate, the lack of any serial arrangement of the abactinal spines, and 

 the seemingly thinner skin. These differences are not important and 

 a good series of specimens may show that the two forms are identical. 

 But it is not desirable to list the South American species from South 

 Africa until the identity is fully demonstrated and I have therefore 

 given the African form a distinguishing name, for the present. 



ECHINASTER RETICULATUS *, Sp. nOV. 



Plate XV. Figs. 1, 2. 



R = 75 mm.; r = 15 mm.; R = 5r; br = 17 mm.; R = 4-5ftr. 

 Disk rather small; arms terete, but slightly flattened. Abactinal 

 skeleton markedly reticulate, the papular areas quite small, and in 



* reticulatus netted, in reference to the network formed by the abactinal plates. 



