432 THE VOYAGE OF H.M.S. CHALLENGER. 
Tonia atlantica, Gray, Ann. and Mag. Nat. Hist., 1840, vol. vi. p. 180. 
Asteracanthion aurantiacus, Miller and Troschel, 1842, System der Asteriden, p. 21. 
Stichaster aurantiacus, Verrill, 1871 (1867), Trans. Conn, Acad. Arts and Sci., vol. i. part 2, p. 293. 
Locality.—Valparaiso. November 1875. On the shore. 
2. Stichaster roseus (O. F. Miiller), Sars. 
Asterias rosea, O. F. Miiller, 1788, Zool. Dan., p. 35, tab. Ixvii. 
Linkia rosea, Thompson, 1840, Ann. Nat. Hist., vol. v. p. 249. 
Cribella rosea, Forbes, 1841, Hist. Brit. Starfishes, p. 106. 
Asteracanthion roseus (pars), Miiller and Troschel, 1842, System der Asteriden, p. 17. 
Stichaster roseus, Sars, 1861, Oversigt af Norges Echinodermer, Christiania, p. 86. 
A number of examples of this species were collected during the “ Porcupine” Expedi- 
tion, but no record is given of the Station or depth at which they were obtained. 
3. Stichaster albulus (Stimpson), Verrill. 
Asteracanthion roseus (pars), Miiller and Troschel, 1842, System der Asteriden, p. 17. 
Asteracanthion albulus, Stimpson, 1853, Syn. Mar. Invert. Grand Manan, p. 14. 
Asteracanthion problema, Steenstrup, 1855, Videnskab. Medd, naturh. Foren. i Kjgbenhavn f. 1854, 
p. 240. 
Asterias albula, Stimpson, 1863, Proc. Acad. Nat. Sci. Philadelphia, p. 142. 
Stichaster albulus, Verrill, 1866, Proc. Boston Soc. Nat. Hist., vol. x. p. 351. 
Stephanasterias albula, Verrill 1872 (1871), Bull. Essex Institute, vol. iii. p. 5. 
Locality.—Station 49. South of Halifax, Nova Scotia. May 20, 1873. Lat. 43° 
3’ 0” N., long. 63° 39’ 0” W. Depth 85 fathoms. Gravel, stones. Bottom temperature 
35°°5 Fahr. ; surface temperature 40°°5 Fahr. 
& 
4. Stichaster polyplax, Miiller and Troschel, sp. 
Asteracanthion polyplax, Miiller and Troschel, 1844, Archiv f. Naturgesch., Jahrg. x., Bd. i., p. 178. 
Asterias polyplax, Perrier, 1875, Révis. Stell. Mus., p. 63 (Archives de Zool. expér., t. iv. p. 327). 
Locality.—Station 162. Off East Moncceur Island, Bass Strait. April 2, 1874. Lat. 
39° 10’ 30” S., long. 146° 37’ 0” E. Depth 38 to 40 fathoms. Sand and shells. Surface 
temperature 63°°2 Fahr. : 
Remarks.—The structure of this form necessitates, in my opinion, its removal from 
the genus Asterias; and on these grounds I have classed it with Stichaster, although I 
am inclined to think that when more is known of the anatomy of Stichaster, the estab- 
lishment of a subgenus, if not actually a distinct genus, may be required for the reception 
of Asteracanthion polyplax, in which probably some other forms now placed under 
Astervas may also ultimately be included. 
