44 HOLOTHURIOIDEA. 
edge, afew small perforations, the length of which is in the opposite 
direction to that of the radiating openings, each of them forming a 
minute segment of a semicircle. 
“ Tentacula 10 (8 long and 2 very short}, completely clothed in 
a scaly investiture of irregular-shaped cribriform calcareous plates. 
“ Found in St. Magnus Bay, and also on the Balta Haddock- 
ground.” 
I have not seen this species. 
4. PSOLUS. 
Psolus, Oken, Lehrb. Naturg. iii. (1815) p. 352; Selenka, Zeit. wiss. 
Zool, xvii. (1867) p. 842; Lampert, Seewalzen, (1885) p. 17; Théel, 
Chall. Rep, Hol. (1886) p.126; Ludwig, Klass. u. Ordn. (1891) p- 350. 
Cuviéries, Peron, sec. Curier, Rigne An. iy. (1817) p. 22 fn. 
Cuvieria, "Tiger, De fol. (1833) p- 20; de Bl. Actinol. (1854) p. 191; 
Brandt, Prodr. descr. (1835) p. 47; Verrill, Proc. Bost. Soc. N. H. 
x. (1866) p. 353. 
Lepidopsolus, Bronn, Klass. uw. Ordn. ii. (1860) p. 404. 
Lophothuria, Verrill, Proc. Bost. Soc. N. H. x. (1866) p. 353. 
Lissothuria, 7d. Trans. Connect. Acad. i. (1867[71]) p. 522. 
A dendrochirotous form with ten tentacles, in which the trivial 
surface is flattened to a sole and alone carries podia. 
Key to the Species. 
Podia in three complete rows .........00+ 1. P. phantapus. 
Podia of median row few or none ........ 2. P. fabricn. 
1. Psolus phantapus. (Plate VI. fig. 1 & Plate VIII. fig. 4.) 
Holothuria phantapus, Strussenfeldt, Vet.-Ak. Hdlg. xxvi. (1765) 
p. 263, pl. 10; Limneus, Syst. Nat. xii. (1767) p. 1089; O. F. Muller, 
Zool. Dan. iii. (1788) p. 54, pls. exil. ‘ exi. ; Dal, yell, Powers of 
the Creator, (1851) p. 79, pl XV. 
Ascidia rustica ?, Pennant, Brit. Zool. iv. (1777) p. 40, pl. xxiii. 
fig. 35. 
Ascidia eboracensis, 7d. Brit. Zool. (1812) p. 99, pl. xxv. fig. 3. 
Cuvieria phantapus, Fleming, Brit. An. (1828), p. 483 ; Diib. &§ Kor. 
Vet.-Akad, Hdlg, 1844 (1846) p. 315. 
Cuviera phantapus, Johuston, Loudon’s Mag. ix. (1836) p. 472, 
fig. 68. 
L’Holothurie phantope, de Bl. Dict. Sct. Nat. 1x. (1830) p. 175. 
Psolus phantapus, Jiger, de Hol. (1833) p. 21; Forbes, Brit. Starf. 
(1841) p. 203; Gray, Brit. Rad. (1848) p. 9; Maitland, Faun. 
Belg. (1851) p. 96; Stimpson, Inv. Grand Manan, (1853) p. 16; 
Thompson, Nat. Hist. Irel. iv. (1856) p. 442; Liithen, Vid. Meda. 
1857, pp. 12 & 68; Sars, Norg. Ech. (1861) ?. 112; Selena, Leit. 
wiss. Zool. xvii. (1867) p. 342, pl. xix. figs. 94 & 95; Semper, 
fol. (1868) p. 272; Norman, Rep. Brit. Assoc. 1868 (1869), p. 316 ; 
Duncan § Sladen, Echinod. Arctic Sea, (1881) p. 10; Bell, P. Z. 8. 
1882, p. 646; Lampert, Seewalzen, (1885) p. 116; Théel, Chall. 
Rep. Hol, (1886) p. 127. 
Body moderately curved, hinder portion often greatly constricted 
