EASTERN TROPICAL PACIFIC ASTEROIDEA. 87 
PTERASTERIDAE. 
Although there are only two specimens of this family in the collection, 
their identification has necessitated a critical revision of the genus Hymenaster 
and it has seemed worth while to publish this revision. The first reference to 
the group in literature occurs in Wyville Thomson’s The Depths of the Sea, 
published in 1873, but it was really the work of the CHALLENGER, in the same 
and three subsequent years, which revealed what a wide-spread and character- 
istic deep-sea genus Hymenaster is. Since that day numerous additional spe- 
cies have been taken, until the number which have been named now reaches a 
total of forty-four. The following list gives these species in their chronological 
order with the necessary bibliographical references and the locality and depth 
at which they were first taken. 
List of the specific names used with Hymenaster. 
pellucidus WyviLtE THomson, 1873. Depths of the Sea, p. 120. Faerée Channel, 580 fms. 
nobilis WxvILLE THomsen, 1876. Journ. Linn. Soe. Zool., 13, p. 73. 1,099 miles southwest of Australia, 
1,800 fms. 
membranaceus WYVILLE THOMSON, 1877. The Atlantic, 1, p. 108.1 Off Portugal, 1,125 fms. 
formosus SLADEN, 1882. Journ. Linn. Soc. Zool., 16, p. 213. 1,099 miles southwest of Australia, 1,800 
fms. 
pergamentaceus SLADEN, 1882. Ibid., p. 215. East of Buenos Ayres, 2,650 fms. 
sacculatus SLADEN, 1882. Ibid., p.217. 1,099 miles southwest of Australia, 1,800 fms. 
echinulatus SLADEN, 1882. Ibid., p. 218. Mid-South Pacific, 2,335 fms. 
carnosus SLADEN, 1882. Ibid., p. 220. Off Chili, 1,500 fms. 
glaucus SLADEN, 1882. Ibid., p. 221. Southwest of Suruga Gulf, Japan, 565 fms. 
vicarius SLADEN, 1882. Ibid., p. 223. Between Juan Fernandez and Valparaiso, 1,375 fms. 
infernalis SLADEN, 1882. Ibid., p. 224. Mid-North Pacific, 2,900 fms. 
caelatus SLADEN, 1882. Jbid., p. 225. 1,099 miles southwest of Australia, 1,800 fms. 
crucifer SLADEN, 1882. Ibid., p. 227. 1,099 miles southwest of Australia, 1,800 fms. 
anomalus SLADEN, 1882. Ibid., p. 228. North of Tristan da Cunha, 1,425 fms. 
latebrosus SLADEN, 1882. JIbid., p. 230. Southwest of Australia, 1,950 fms. 
porosissimus SLADEN, 1882. Ibid., p. 231. Between Juan Fernandez and Valparaiso, 1,375 fms. 
graniferus SLADEN, 1882. Ibid., p. 238. Between Marion and Crozet Islands, 1,375 fms. 
geometricus SLADEN, 1882. Ibid., p. 234. Mid-South Pacific, 2,335 fms. 
pullatus SLADEN, 1882. Ibid., p. 235. Southwest of Admiralty Islands, 1,070 fms. 
coccinatus SLADEN, 1882. Ibid., p. 238. Between Marion and Crozet Islands, 1,375 fms. 
praecoquis SLADEN, 1882. Ibid., p. 240.2 Near Crozet Islands, 1,375-1,600 fms. 
modestus VERRILL, 1885. Amer. Journ. Sei. ser. 3, 29, p. 151.°. Off southern New England, 1,098-1,451 
fms. 
1 Jt is perhaps debatable whether there is an adequate description in connection with this first use 
of the name, but as the points mentioned would probably distinguish the species from the only other 
Hymenasters known at the time, it may be just as well to let the name continue to rest on Wyville 
Thomson’s authority. 
2 These eighteen species described by Sladen, as well as the three named by Wyville Thomson, are 
fully illustrated in Sladen’s Challenger Asteroidea, issued in 1889. 
3 It is doubtful whether this description is adequate. A much better one appeared in 1894, Proc. 
U.S. N. M., 17, p. 277. 
