88 PTERASTERIDAE. 
giganieus SLADEN, 1891. Proc. Roy. Irish Acad., ser. 3, 1, p. 696. Southwest of Ireland, 750 fms. 
giboryi Perrier, 1894. Travailleur et Talisman Stell., p. 189. Between Azores and Europe, 2,218 fms. 
rer PERRIER, 1894. Ibid., p. 1861 Eastern North Atlantic, 623-1,248 fms. 
regalis VERRILL, 1895. Amer. Journ. Sci. ser. 3, 49, p. 203. Off southern New England, 1,374 fms. 
regalis var. agassizii VERRILL, 1899. Trans. Conn. Acad., 10, p. 221. Off southern New England, 
1,242 fms. 
perspicuus Lupwic, 1903. Belgica Seesterne, p. 30. Antarctic Ocean, southwest of Alexander the 
First Land, 222-250 fms. ; 
quadrispinosus FisHER, 1905. Bull. U. S. Bur. Fish., 24, p. 315. Off San Diego, Cal., 1,059 fms. 
platyacanthus Lupwic, 1905. Mem. M. C. Z., 32, p. 191. Panamic region, 1,359-1,572 fms. 
purpureus Lupwic, 1905. Ibid. p. 194. Between Cocos Island, and Panama, 1,470 fms. 
violaceus Lupwic, 1905. JIbid., p. 196. Southeast from Acapulco, Mexico, 1,877 fms. 
gracilis Lupwie, 1905. Ibid., p.198. Panamic region, 1,321-1,771 fms. 
pentagonalis FisHer, 1906. Hawaiian Starfishes, p. 1099. Hawaiian Islands, 289-334 fms. 
roseus KOEHLER, 1907. Bull. Inst. Ocean., no. 99, p. 21. Eastern North Atlantic, 1,009-1,148 fms. 
campanulatus Korner, 1908. Trans. Roy. Soc. Edinburgh, 46, p. 550. Weddell Sea, 1,410 fms. 
densus KoEHurr, 1908. Ibid., p. 554. Weddell Sea, 2,620 fms. 
edax Koruter, 1908. Ibid., p. 552. East of South Orkney Islands, 1,775 fms. 
fucatus Korn.er, 1908. Ibid., p. 553.2 Weddell Sea, 1,410 fms. 
alcocki Korner, 1909. Investigator Deep Sea Ast., p. 110. East side, Bay of Bengal, 643 fms. 
koehleri Fisner, 1910. Ann. Mag. Nat. Hist., ser. 8, 5, p. 170. Bering Sea, 1,771 fms. 
perissonotus FisHEr, 1910. - Ibid., p. 170. Off San Diego, California, 984 fms. 
barischi FisHer, 1916. Proc. Biol. Soc. Washington, 29, p. 29. Sulu Sea, 1,105 fms. 
rhodopeplus FisHER, 1916. Jbid., p. 29. Gulf of Tomini, Celebes, 834 fms. 
The form which Verrill described as a variety (agassizit) of regalis seems 
undoubtedly a valid species as it differs from regalis in several fundamental 
points. 
The characters which seem of the most importance in distinguishing the 
species of Hymenaster are the armature of the oral plates and of the adambula- 
cral plates. In most species the number of adambulacral spines, of oral spines, 
and of suboral spines is remarkably constant. In a few cases, we find three 
adambulacral spines where the typical number is two, or four where three is 
usual, and if the number of oral spines is three, there may occasionally be four, 
while if the number is usually four or five it may run up to seven. The number 
and form of the suborals is less liable to diversity, but owing to slight shifts of 
position or some diversity in size, it is often difficult to decide whether the spine 
nearest the inner end of the oral plate is a suboral or the innermost oral. Careful 
consideration of its relation to the other orals will generally determine the 
point however. Thus in carnosus, Sladen says there are two suborals but 
admits that the inner is perhaps an oral; his figure shows that it is best consid- 
ered the innermost oral. In quadrispinosus Fisher, it is possible, as that author 
___ + These two species of Perrier were named and the names were published in 1885 but with no descrip- 
tion or figures; the names therefore must date from 1894. 
* These four species of Koehler were mentioned and named in 1907, Zool. Anz., 32, p. 144, but as 
the diagnoses are wanting or wholly inadequate, the names must date from the full report. The Hymen- 
aster scotiae of the 1909 Zoological Record is a slip of the pen for Hyphalaster scotiae. 
