84 ASTEROIDEA. 
on each side of the median radial line. The disk is large and 
extraordinarily flat. 
1. Palmipes placenta. 
Asterias placenta, Penn. Brit, Zool. iv. (1777) p. 58, pl. xxxi. 
fig. 59 A. 
Asterias membranacea, Retz. Vet.-Akad. Nya Halg. iv. (1783) p. 258 ; 
L. ed. Gmel. Syst. Nat. (1788) p. 3164; Retz. Diss. Spec. Ast. 
(1805) p. 12; Lamk. An. s. Vert. ii. (1816) p- 558; Delle Ch. 
Descr, An. Invert, Sic. cit. iv. (1841) p. 56, v. (1841) p. 122, pl. 127. 
figs. 8-10, 12, 14, 15. 
Asterias cartilacinea, Flem. Brit. An. (1828) p. 4865. 
Anseropoda membranacea, Nardo, Isis, 1834, col. 716. 
Palmipes membranaceus, Ay. Mém. Soc. Me euchat. i. (1836) p. 192 
Forbes, Mem. Wern. Soc. vii. (1839) p. 119, pl. iii. fig. 3; Wiad 
son, Nat. Hist. Irel. iv. (1856) p. 440 ; Duj. & Hup. ‘Echin. (1862) 
p. 373; Fischer, Act. Linn. Soc. Bord. xxvii. (1872) p. 367 ; Perrier, 
Arch. Zool. ate v. (1876) p. 210; Vagwer, Arch. Zool. expér. 
vil. (1878) p. 2 2 ak xiv. figs. 1-5; Ludw. Mitth. zool. Stat. Neap. 
i. (1879) p. dl. sce Proce. Phys. Soc. Edin. 1890-91 (1892) 
82. 
Asteriscus palmipes, M. Tr. Syst. Ast. (1842) p. 39; Heller, Zooph. 
u, Ech, Adriat, Meer. (1868) p. 53; Schmidtlein, Mitth. zool. Stat. 
Neap. 1. (1878) p. 126. 
Palmipes placenta, Norm. Ann. §& Mag. xv. (1865) p. 120; Parfitt, 
Trans. Devon Assoc, v. (1872) p. 359. 
2KR = 37 (nearly). 
A perfectly flat species, liable to a good deal of distortion in 
drying. Of the form of a pentagon with curved or angulated sides ; 
sometimes almost round. Ambulacra rather wide, fringed by a row 
of spines, ordinarily set by fives on each ossicle ; outside these there 
is a transverse row of three or four spines. The ossicles on the 
ventral surface carry from ten to two or three spines according as 
they are near to or far from the mouth; these spines are much 
longer than the much finer and more glossy spinelets, which are 
more numerously represented on the ossicles of the dorsal surface. 
The small, rather obscure madreporite is quite close to the centre 
of the disk. 
Colour red in the centre and at the edges, above and below; 
red along the rays above ; elsewhere white. Gradually fades when 
dead; the red colour quite lost in spirit-specimens, 
R. T. 
93 63°5 
72:5 oll 
70 42:5 
54 32 
40 26 
36 29 
27 21 
The five Rs and vs are frequently respectively different in one and 
the same specimen, 
