CHEILASTER.—LASIASTER. 81 
3. CHEILASTER. 
Marginaster (vox hybr.), Perrier, Bull. Mus. Comp. Zool. ix. (1881) 
p- 16 (n. n.); ad. Nouv. Arch. du Mus. iv. (1884) p. 229; Sladen, 
Chall. Rep. Ast. (1889) p. 364, 
No more than Mr. Sladen, who temporarily accepts the genus, 
can I, who have only seen one specimen, and that one of 12 millim. 
in diameter, add anything to Prof. Perrier’s diagnosis, which does 
not err on the side of length. It runs thus :— 
** Petites astéries pentagonales ou & bras peu marques; ossicules 
recouverts par un tégument mince; ossicules eux-mémes délicats ; 
dordinaire légérement épineux.—Corps bordé par une double rangée 
de plaques marginales bien distinctes.” 
1. Cheilaster fimbriatus. 
Marginaster fimbriatus, Sladen, Chall. Rep. Ast. (1889) p. 365, 
pl. lviii. figs. 4-6. 
R=6; r=5mm. 
Mr. Sladen distinguishes this species as having groups of granules 
on the abactinal plates, but no comb of spinelets on the supero- 
marginal plates ; it has a row of spinelets on the actinal interradial 
areas set parallel to the margin. 
a. 56° 15’ N., 11° 26’ W., 1360 fms, ‘Porcupine’ Exp. (Type.) 
4. LASIASTER. 
Lasiaster, Sladen, Chall. Rep. Ast. (1889) p. 371. 
In cataloguing this genus I must repeat the word of warning I 
gave under Ithegaster, and I must disclaim any share of respon- 
sibility for the introduction of another genus based on two smal] 
specimens, which are recognized as being immature. It differs 
from Jthegaster in having well-developed superomarginal plates, and 
there is consequently a thick wall-like side to the body. All the 
intermediate plates bear isolated groups of spinelets. 
1. Lasiaster villosus. 
Lasiaster villosus, Sladen, Chall. Rep. Ast. (1889) p. 372, pl. lviii. 
figs. 7-10. 
I am unable to deduce from Mr. Sladen’s description the specific 
diagnosis of this form, and as the only two specimens I have seen 
are immature I cannot draw up one myself. The figures will show 
the student all he can be told. 
a, b. 59° 34' N., 7° 18' W., 542 fms. ‘Porcupine’ Exp. (Types.) 
