DALL: MOLLUSCA AND BRACHIOPODA. 311 
The opereulum is typically Columbelloid, having an ovate margin of polished 
callus with a narrow ray of callus projecting across the centre of the scar of adhe- 
Sion. The animal is whitish with a reddish-brown margin to the.mantle; the 
tentacles are rather short and stout, with the eyes on short, separate pedicels just 
outside the tentacles ; the proboscis wholly retractile, the foot large, voluminous, 
solid, with wrinkled surface and an apparently rather blunt posterior extremity. 
Muricidae. 
PURPURINAE, 
THAIS BOLTEN. 
(= Purpura Lamarck, 1799, not Martyn, 1784.) 
Thais nesiotes Darr, n. sp. 
Shell small, purple-brown, bleaching to a purplish-white, with four smooth, 
minute dark brown nuclear whorls and about four subsequent whorls; suture 
appressed with a slight ridge, followed by a slight constriction, in front of it; 
aperture longer than the spire, which is acute; whorls moderately rounded ; spiral 
sculpture of numerous flattish major spiral ridges, sometimes striated or even 
duplex, with narrower ehannelled interspaces usually with a small intercalary 
thread; on the penultimate whorl there are five or six major spirals between the 
sutures and on the last whorl about fourteen; these are crossed by very numer- 
ous slightly elevated lamellae, which in well preserved specimens imbricate the 
interspaces and rise a little higher at the suture; aperture semilunate, narrow 
behind; outer lip more or less thickened, white, and obscurely dentate within; 
columella broad with a flattened white callosity; pillar short, straight; canal 
very short and narrow, but having a strong siphonal fasciole with a closed chink 
behind the columellar callus, Lon. of shell, 18; of last whorl, 15; of aperture, 
11; max. diam. 10.5 mm. 
Jollected on the shore at Easter Island by the ‘ Albatross ' 
Mus. 110,766. 
A thorough search has failed to reveal this little species anywhere among the 
described species of Purpura. The specimens are possibly not quite mature. 
, 
party. U. S. N. 
MURICIN AE. 
TROPHON Monrrort. 
Trophon (Pascula) citricus Dax, n. sp. 
Shell small, fusiform, acute, the spire longer than the aperture, livid flesh color 
with orange knobs and aperture, and about six whorls; apex rather acute, but in 
all the specimens overgrown with nullipore, ete., or eroded so as to be inaccessi- 
