336 CHARLES LincoLn EDWARDS, 
ofthe introvert retractors, and thus one-fifth of the length 
of the drawing in front of where they actually exist! Just how 
the stone-canal and Polian vesicles, which are properly located in 
the drawing, enter the misplaced ring-canal, is a mystery. 
According to ForBes, 1841, the Shetland fishermen class this sea- 
cucumber as Pushen (poison) and throw it away as unlucky and 
dangerous but Stımpsox, 1851—1854, regards it „when boiled, quite 
as palatable as lobsters“. The latter author, 1853, reports this 
species at Grand Manan just below the ordinary low-water mark 
on rocky shores and exposed at spring tides. Sometimes areas of 
several square rods are entirely occupied by them, and he also says, 
1851—1854, „They usually adhere to the bare surface of the rocks 
by the suckers of one side of the body (which is always of a lighter 
hue than the other side), but they are pleased to find a chink, or 
some pebbles, in which to bury themselves, when nothing can be 
seen of them but their tentacula; ten beautiful purple tufts radi- 
ating from a center and occupying a circle of six inches in dia- 
meter“, 
In addition to the above authors, more or less complete de- 
scriptions have been given by FoRrBES & Goopsır, 1839; DüBEN 
& KorEn, 1846, 1846a ; Dawverı, 1851; Avkes, 1851; Lürken, 1857; 
SELENkA, 1867; SEMPER, 1868; Duncan & SLADEN, 1881; LAMPERT, 
1885; LEVvIssen, 1886; TH&EL, 1886; KoEHLER, 1895; MICHAILOVSKIJ, 
1902, 1904; CLARK, 1904; and Epwarnps, 1907, 1909. 
The following authors have added to the habitat very short 
deseriptions with nothing new, or of especial importance; — MÜLLER, 
1776, 1788, 1806; Linn&, 1788—1793; LamArck, 1816; BLAINVILLE, 
1822, 1830, 1834; JÄGER, 1833; Sars, 1850; Ayres, 1855; FoRBES 
& GooDwINn-AUSTEN, 1859; VERRILL, 1866 ; NoRMAN, 1868; POURTALES, 
1869; M’Intos#, 1875; Duncan & SLADEN, 1877; KÜKENTHAL & 
WEISSENBORN, 1886; KnirovicH, 1901; Rankın, 1901 and CLArk, 1901a. 
The habitat only is given by the following authors, and 
when any author is not certain of the identification, a ? precedes 
his name; — Encyl. möth. Hist. Nat. des Vers, 1827; Taomr- 
son, 21840, 1844 ; ?Gourn, 1841; Sars, 1850, 1858, 1861; 
Forges, 1852; McAnprew & BARRETT, 1857; Stımpson, 1857, 1863; 
F. Dusarpın & H. Hur£, 1862; PackAarD, 1867; VERRILL, 1867, 1871, 
1879, 1885; Heucuın, 1874; Norman, 1876, 1901, 1903; L3suUNnGMANn, 
1879; DAnIELSSEN & Korn, 1882; Lupwıg, 1882, 1883, 1898, 1900; 
Ganong, 1884; JARZYNSKY, 1885; ? MurDock, 1885; FiscHEr, 1886; 
