324 BULLETIN 100, UNITED STATES NATIONAL MUSEUM. 



smaller plates, abnormally, does not invalidate it, in my opinion, as 

 a generic character. A similar variation may occur in Pentagonaster 

 Gray. The growth of the marginal plates must be different from that 

 of Calliaster and MilteUphaster^ where the superomarginals decrease 

 in size regularly and gradually at the end of the series. 



Genus GONIODISCASTER Clark. 



Ooniodi^caster H. L. Clabk, 1909, p. 110. Type, Goniodiscus pleyadella 

 (Lamarck). 



GONIODISCASTER FORFICULATUS (Perrier). 



Plate 80, figs. 2, 3. 



Ooniodisous forficidatus Peeriek, 1875, p. 234. — Koehler, 1910a, p. 61, pi. 7, 

 tigs. 1, 2, and 3 ; pi. 11, fig. 1 ; pi. 14, fig. 2. 



Azotes on Philippine specimens, — Koehler has very fully described 

 and illustrated the specimens from India, and has noted wherein 

 these depart from the types, of which he had photographs. He 

 states that figures 2 and 3, plate 7,^ agree very closely with Perrier's 

 type. The two Philippine specimens also show close resemblance 

 to these figures. 



Koehler writes that his specimens varied somewhat, and I have 

 been able to compare the example from station 5159 with the Indian 

 specimen from station 78, coast of Ganjam (Bay of Bengal, south 

 of Puri), the latter example being now No. 2094, Museum of Com- 

 paratize Zoology. This example shows a number of differences to 

 the Philippine specimens, which will be noted below. 



Specimen from station 5159. R=37 mm., r=15 mm., R=2.4 r. 

 The general features are sufficiently shown by the figures. The mid- 

 radial line of plates is clearly distinguishable, almost conspicuous, 

 as are also the double series of 3 plates (6 in all) extending from 

 the " primary basal " to the superomarginals. The median plate of 

 each of these series is the largest, and the double series is common 

 to a number of species of this genus. The midradial series of plates 

 sometimes reaches the terminal plates, sometimes is prevented by the 

 last pair of superomarginals meeting on the radial line. A single 

 series of adradials usually extends as far as the third superomarginal 

 from the end. A second parallel series, however, does not extend 

 beyond the third superomarginal. The small globular and thimble- 

 shaped granules are distinctly spaced, at least half the width of the 

 granule, sometimes more, those on the midradial plates being smallest. 

 The granules increase in breadth and length rather abruptly on the 

 adradial plates, although the difference is not gi-eat. The marginal 

 granules are lower and broader than the adradial and roundish or po- 

 lygonal in outline. There are two kinds of abaci inal pedicellariae — 



1 Koehler, 1910a, p. 61. 



