250 Annals of the South African Museum. 



due to their larger size, while the degree of projection of the infero- 

 inarginal plates and the exact form of their spines is a matter of in- 

 dividual diversity. Bell (1905, Mar. Inv. South Africa, vol. 3, p. 243) 

 records pontoporams from 21 stations and rapensis from one, but lie 

 does not hint at the means by which lie distinguished them. 



P.P. 15835. Cape Point, N.W. 5 miles. 47 fuss. Sand and rocks. 

 4 specimens; adult? 



* ASTROPECTEN HEMPRICHII. 



Miiller and Troschel, 1842. Syst. Ast., p. 71. De Loriol, 18S5. 

 Cat. Rais. Ech. Mauritius: Stellerides, jil. 21, figs. 7-8. 



This species is reported by Peters (1852) from Inhambane, P.E.A. 

 and by Bell (1884) from Mozambique. I have not myself seen 

 specimens from the African coast, south of Zanzibar. 



ASTROPECTEN GRANULATUS. 



Miiller and Troschel, 1842. Sys. Ast, p. 75. Diiderlein, 1890. 

 Jena Denksch., vol. 8, lief. 3, pi. 18, figs. 30, 30a. 



These South African specimens were at first identified with mona- 

 canthits Sladen but in the larger specimens the paxillae always show 

 several to many central granules, and Sladen emphasizes the single 

 central granule as an important species character. Koehler however 

 has stated that the number of central granules on the paxillae is a 

 matter of age and examination of these specimens satisfies me that 

 he is correct. Careful study of his text and figures, and those of 

 Doderlein, with Sladen's, convinces me that monacanthus is identical 

 with granulatus. The only point on which I am doubtful is the 

 coloration, gome specimens (none from South Africa however) showing 

 a conspicuous mottling of the upper surface. This mottled form is 

 figured by Sladen as granulatus and Koehler says his specimen from 

 the Aru Islands is exactly like it in color. On the other hand he 

 says his specimen is identical with that figuied by Doderlein from 

 Torres Strait and Doderlein's specimen is unicolorous. Probably the 

 coloration is more or less subject to individual diversity. The length 

 of the superomarginal plates and the extent to which they occupy 

 the dorsal sin-face of the arms is a matter of age; they are longest 

 and dorsally most conspicuous in the smallest individuals before me 

 (R = 7 - 5 mm); they are relatively shortest and least visible from 

 above in the largest specimens (R = 38 mm). These large specimens 

 are just the size of Koehler's from the Aru Islands, and considerably 

 larger than those seen by Sladen and Doderlein, but they are smaller 



