ECHINOCARDIUM, 171 
antero-lateral series six to eight, and in the hinder from twelve to 
fifteen ; the outer postero-lateral series has fourteen, and the inner 
twelve; but these numbers must not be taken to be quite constant ; 
these ambulacra are about flush with the test. 
The periproct is an irregular oval, with the long axis at right 
angles to a vertical line ; the subanal fasciole seems to include only 
one pair of plates, which are triangular in form and have a pair of 
pores at the outer apex of each triangle; the spines carried on them 
are more prominent than in &. cordatum; the bare ambulacral 
spaces below are rather narrow. 
The tubereulation is a good deal finer on the upper than on the 
lower surface, but on each, respectively, it is very uniform. 
Test. 
(a Greatest diameter of 
Greatest lm —<—$—_——_— — 
length. Breadth. Height. Peristome, Periproct. 
67 70 45 17°5 15 
63 65 43 16 
57°5 15) 40 12:5 
Distribution. Both sides of Atlantic, but known only from 
Shetland, North Sea, English Channel, West Indies, and Florida. 
Shallow water to 120 fms. 
a, 6. Scilly Islands. 
ce. Jersey. Prof. Bell. 
d, e. Jersey. 
3. Echinocardium flavescens. (Plate XVI. figs. 6 & 7.) 
Spatagus flavescens, O. F. Mill. Prod. Zool. Dan. (1776) p. 286. 
Spatangus ovatus, Fem. Mem. Wern. Soe. y. (1824) p. 287, pl. vi. ; 
id. Brit. Anim, (1828) p. 480; de Bl. Actin. (1834) p. 202; 
Desmil. Syn, (1837) p. 888. 
Amphidetus ovatus, Dib. § Kor, Vet-Akad. Hdlg. 1844 (1846), 
p- 283, pl. x. fig. 50; Ag. § Des. Ann. Sci. Nat. viii. (1847) p. 12; 
Sars, Norg. Ech. (1861) p. 98; Perr. Ann. Sci. Nat. xiii. (1869) 
p. 70, pl. vi. fig. 2; Jarzynsky, Trans. Petersb. Soc. Nat. i. (1870) 
». B19. 
Pet ocastiuse ovatum, Gray, Brit. Rad. (1848) p. 6; td. Cat. Ree. 
Ech. (1855) p. 43; Duy. § Hup. Echin. (1862) p. 602; Al. Ag. 
Bull. Mus. C. Z. i. (1869) p. 276. 
Echinocardium flavescens, Al, Ag. Rev. Ech. (1872) pp. 110 & 351, 
pl. xx. figs. 3& 4; Gauthier, C. R. Ixxix. (1874) p. 402; Mob. § 
Biitsch. JB. Comm. Kiel, ii. & iii. (1875) p. 150; Ludwig, Mitth. 
Stat. Neap. i. (1879) p. 561: Al. Ag. Chall. Ech. (1881) p. 175; 
id. Proc. R. Soc. Ed. xi. (1880-82) p. 698; Koehler, Ann. Mus. 
Marseille, i. 3. (1883) p. 129; Carus, Prod. Faun. Mediter. (1884) 
p- 103 ; Herdman, Rep. Faun. Liverp. Bay, (1886) p. 138 ; Barrois, 
Rev. Biol. i. (1889) p.110; Scott, Proc. R. Phys. Soc. Edinb. 1890-91 
(1892), p. 82. 
Amphidotus roseus, Forbes, Brit. Starf. (1841) p. 194; Thomps. 
Nat. Hist. Irel. iv. (1856) p. 442. 
Test rather oblongo-ovate than cordiform in shape; anterior 
