CILARACTERISTIC DEEP-SEA TYPES. CRINOIDS. 123 
Hyocrinus, and Ilyerinus; but the “ Blake” was not fortunate 
enough to obtain any of these. 
The last and perhaps most interesting of the West Indian 
stalked erinoids belongs to the genus Holopus. (Figs. 413, 414.) 
Less than half a dozen specimens of it are known to exist. The 
first specimen collected is now in the museum of the École des 
ar i Fig. 414. — Half-grown Holopus Rangi. 
Fig. 413. — Adult Holopus Rangi. 13, 3. (Carpenter.) 
(Carpenter.) 
Mines. Sir Rawson W. Rawson, when Governor of Barbados, 
obtained three specimens, which were lent to Sir Wyville Thom- 
son, and have, with the material of the “ Blake,” formed the 
basis of Dr. Carpenters work on the subject. 
The genus Holopus was established by D'Orbigny, in 1837, 
from a single specimen which was brought from Martinique by 
Sander Rang. Its true nature was not recognized by other 
palwontologists, some of whom considered it to be a barnacle. 
The dried specimens all have a blackish green tinge ; the single 
arm dredged off Montserrat had a whitish tint. The arms of 
all the specimens are strongly curved, closing the disk entirely ; 
but of course this is not the natural attitude of the animal. 
Holopus is attached by an irregularly expanded base, formed by 
the extension of the tubular calyx, which is slightly bent, while 
a constrietion separates the cup from the spreading base. The 
youngest specimen (Fig. 415), of jet-blaek color, dredged off 
Bahia Honda, only 3 mm. in diameter, differs very much from 
the older specimens, as will be seen from the figures. The 
