URANASTKR, RAMSEYENSIS. 109 



2. Uranaster ramseyensis (Hicks). Plato VI, figs. 1 — 1; Text-figs. 64 — 66. 



1873. Palasterina ramseyensis, Hicks, Quart. Journ. Geol. Soc, vol. xxix, p. 51, pi. iv, figs. 21 — 23. 



1874. „ ,, Woodward, Geol. Mag., dec. ii, vol. i, p. 96. 



1914. Palasterina? ,, Schuchert, Fossilium Catalogus, Animalia, pt. 3, p. 31. 



1915. Palasterina ? „ Schuchert, Bull. 88, U.S. Nat. Mas., p. 154. 



Material. — Two specimens of the species are known, both of which have a 

 counterpart. They are from the Lightbody Collection, and are in the Museum 

 of the Victoria University, Manchester. L. 11036'? is the original of Hicks' fig. 21 ; 

 its counterpart is L. 1 1038. L. 11037 is the original of fig. 22, and its counterpart 



S,M, 



Text-fig. 64. — Wash drawing of a portion of the apical surface of Uranaster ramseyensis (L. 11038). 

 I.M., infero-marginalia ; R., radialia ; S.M., supero-marginalia. x 5. 



is L. 11036/>. The original of fig. 22, L. 11037, is chosen by me as the holotype of 

 the species. 



Specific Characters. — Much smaller than U. h'nahani, r measuring 4 mm. 

 Adambulacralia from base of arm onwards outnumber the infero-marginalia. 



Apical Surface (Plate VI, figs. 2, 4; Text-fig. 64). — The apical surface 

 of the arm is strikingly similar to that of U. hlnahani, most of the essential 

 differences being those which we should expect to find in a more primitive form 

 from a lower geological horizon. As in V. kinahani and Petraster speciosus the 

 boundary of the apical surface is formed, not by the supero-marginalia, but by 

 the infero-marginalia (compare the Text- fig. 64 with Text-fig. 60, p. 106, and 

 Text-fig. 67, p. 111). The supero-marginalia in the disc are stellate in the 

 three species (compare the same Text-figures). The radialia are more persistent 

 and more readily recognisable in JJ. ramseyensis than in U. kinahani (compare 

 Text-fig. 64 with Text-fig. 61, p. 106). This would be expected because the 



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