140 ECHINOIDEA. 
Leiocidaris papillata, Duj. § Hup. Ech. (1862) p. 485; Perr. Ann. 
Sct. Nat. xiii. (1870) p. 24. 
Orthocidaris papillata, A. Ag. Bull. Mus. C. Z. i. (1863) p. 17. 
Dorocidaris papillata, A. Ag. Rev, Ech, (1872-3) pp. 105 & 254, 
pls. i., i. 6, i. a. figs. 1-18, il. b. tigs. 1-5, ii. ¢. figs. 7-12 ; id. Bull. 
Mus. C. Z, viii. (1878) p. 70; Ludwig, Mitth. oer Stat. Neap. i. 
(1879) p. 554; Stewart, Trans. Linn. Soc. i. (1880) p. 569, pl. 70. 
figs. 1-5; A. “ly. Chall. Rep. Ech, (1880) p. 40; Ludw. Zeits. f. 
w. Zool. Xxxiv. (1882) p. 85, pl. ili. figs. 8-10; Verrill, Am. J. Set. 
xxul, (1882) p. 133; A, Ag, Proc. Roy. Soc. Fa. vl. (1883) p Oo fe 
Koehler, Ann. Mus. Marseill. i. 3, (1885) p. 118, pl. iii. He lige 
Rathbun, Proc. US, Nat. Mus, viii. (1885) p. 611; Prouho, CR. 
cil. (1886) p- 1408 ; ed. Arch. Zool. expér. v. (1887) p. 217, pls. 14- 
21, 23-25. 
Cidarites hystrix, Lamk, Anim. s. Vert. fecal a p- 55; td. op. cit. 
(1840) il. p. 879; Desm. Etudes (1851) p 
Cidarites (Phyllacanthus) hystrix, Br “nee Py dr, descr. Anim. 
(1836) p 
Cidaris eee De Blainv. Actinol. (1832) p. 231, pl. xx. bis, fig. 5; 
Phil. Arch. f Nat. xi, (1845) p. 853; Ag. Ann. "Sei. Nat. vi. (1846) 
p. 32; Sars, Nyt Mag. x. (1859) p. 53; Lovén, op. cit. p. 29, a 5.0. 
feller, Zoophyt. u. Lchinod. adriat. Meer. (1863) p- 69. 
Leiocidaris hystrix, Du). § Hupé, Hist. nat. Echin. (1862) p. 484. 
Orthocidaris hystrix, A. dg. Bull. Mus. C. Z. i. (1865) p. 17. 
Dorocidaris hystrix, A. Ag. Rev. Echin. (1872) p. 105. 
Dorocidaris abyssicola, 7d. Bull, Mus. C. Z. i. (1869) p. 253. 
Cidaris borealis, Duben §& Koren, Utfv. Vet.-Ak. Forh. 1844 (1845), 
p dA: 
Gass affinis, Phil. Arch. f. Nat. x. (1845) p. 3853; Sars, Nyt 
Mag. x. (1859) p. 54; Wyv. Thomson, Phil. Miran. clxiv. (1874) 
Dy A205 pleas 
Giannis aon Ag. Ann. Sct. Nat. vi. (1846) p. 32; Heller, Zoophyt. 
u. Echinod. adriat. Meer, (1868) p. 69; Perrier, Ann. Sci. Nat. xiii. 
(1870) p. 26, pl. ii. fig. 6. 
Rhabdocidaris hystrix, De Lorioit, Mém. Soc. Phys. et d@ Hist. nat. 
Geneve, xxviii. (1883) no. 8, p. 7. 
Primary spines are few in number, vary in colour from pale straw 
to reddish brown, may be twice as long as the diameter of the test, 
but are shorter above and below the ambitus, vary somewhat in 
thickness and in the extent to which they are compressed at the 
tip; the serration of the spines, caused by the granules on their 
surface, is scarcely ever pronounced. There is generally a delicate 
pink band at the base of the spine. Round the tubercle to which 
the spine is attached are set a number of spatulate spines, light 
yellow to dark brown in colour, often darkest in the middle line or 
at the tip. The ambulacral spines are less numerous and smaller 
than the interambulacral secondaries, while those on the apical area 
may be like either, and those on the buccal membrane are like the 
former. 
The test is flat above, circular in outline; ambulacra slightly 
sinuous, not wide; there is no groove connecting the members of 
each pair of pores, but there is a transverse ridge along the upper 
side of the perforate portion of each ambulacral plate. The inter- 
ambulacral area is covered by two regular rows of tubercles and two 
more internal and more irregular rows. There are eight or nine 
