98 ASTEROIDEA. 
Neuch. i. (1836) p. 191; Forbes, Mem. Wern. Soe. viii. (1839) 
RPA 
Uraster, Forbes, Brit. Starf. (1840) p. 78. 
Asteracanthion, M. Tr. Ber. Ak. Berlin, 1840, p. 101; wd. Syst. Ast. 
(1842) p. 14 (pars). 
Diplasterias, Perrier, Miss. Scient. Cap Horn, vi. (1891) p. & 77. 
Arms five, or, if more, not fused so as to form a large disk; the 
abactinal skeleton well developed and bearing spines, but not 
tubercles. 
I have (P. Z. 8. 1881, p. 499) made an artificial scheme for the 
especial object of determining the numerous species of this large 
genus, but I cannot follow Prof. Perrier (Miss. Scient. Cap Horn, 
Kchinodermes [1891], p. & 77) in his division of the genus into 
Diplasterias, defined as having ‘‘ Deux rangées de piquants adambu- 
lacraires au moins,” and Asterias, defined as having ‘“ Une seule 
rangée de piquants adambulacraires ou les piquants alternativement 
isolés et groupés par deux sur les plaques adambulacraires.” This 
division is, I think, fully met by my groups of “ Monacanthida ” 
and ‘ Diplacanthida.” 
Key to the Species. 
Spines on upper surface few and large, or moderate 
and rather more numerous, 
a. Major pedicellariz scattered .......5...+...% 1. A. glacialis. 
6. Major pedicellarize confined to neighbourhood of 
ambulacrallignoOvye ssa carchr citys: op ne 2. A, muellerc. 
Spines small, numerous, irregular. 
Ge APMSTOUNGE! i c1s sreyeis.5' ebm wane ei marsha eleueleys 3. A. rubens. 
beers HatieMed: ie aire vest a ccevele tony stoemacge ite teca te 4. A. murray?. 
ce. Arms short and squat ....... io ecceuimt rea cles 5. A. hispida. 
1. Asterias glacialis. 
Asterias glacialis, Linn. Syst. Nat. x. (1758) p. 661; 2d. op. cit. xii. 
p. 1099; id. ed. Gimel. (1789) p. 3162; O. F. Miill. Zool. Dan. 
(1776) p. 234; Lamk. An. s. Vert. ii. (1816) p. 561; Gray, Ann. § 
Mag. vi. (1840) p. 179; ad. Brit. Rad. (1848) p. 17; Jarzynsky, 
Trans. Petersb. Soc. Nat. i. (1870) p. 518; Ludwig, Mitth. zeol, 
Stat. Neap. i. (1879) p. 5387; Greef, Zool. Anz. v. (1882) p. 117; 
Bell, op. cit. p. 282; Perrier, Ann. Sct. Nat. xix. (1885) no. 8, 
p. 15; Barrows, Rev. Biol. i. (1888) p. 69. 
Asteracanthion glacialis, M. Tr. Syst. Ast. (1842) pp. 14 & 126; 
Dib. §& Kor. Vet.-Akad. Hdilg. 1844 (1846), p. 240; Sars, Nyt 
Mag. x. (1859) p. 51; 2d. Norg. Ech. (1861) p. 87; Lorenz, SB. 
Ak, Wien, xxxix. (1860) p. 677; Dy. § Hup. Ech, (1862) p. 330; 
Fischer, Actes Soc. Linn. Bordeaux, xxvii. (1869) p. 3864; Moeb. 
& Biitschli, TB. Comm. Kiel, ii. & iii. (1875) p. 147. 
Uraster glacialis, Forbes, Brit. Starf. (1840) p. 78; id. Rep. Brit. 
Assoc. 1843 (1844), p. 149; Thompson, Nat. Hist. Irel. iv. (1856) 
. 458. 
eS spinosa, Penn. Brit. Zool. iv. (1777) p. 53. 
Asterias angulosa, O. F. Miill. Zool. Dan. (1788) 11. p. 1, pl. xli. 
Asterias echinophora, Delle Chiaje, Mem. An. Nap. ii. (1825) p.356, 
pl. xviii. fig. 6. 
Stellonia angulosa, dg. Mém. Soc. Neuch. i. (1836) p. 192. 
