172 PLEUROTOMA. 
relationship with jubata, Hinds. The chief differences are the 
narrower form, larger tubercles and shorter canal.” As jubata 
is known to vary considerably in the above characters, acutt- 
gemmata had better be considered a synonym. 
P. EMENDATA, Monterosato. PI. 4, fig. 47. 
Shell brown, the spire-whorls with three cingule and two lire, 
the last whorl spirally multicingulate and longitudinally lirulate ; 
suture slightly but distinctly incised; aperture white within, 
canal short and wide, sinus wide, between the first and second 
carina. L. 9, diam. 3 mill. 
Mediterranean Sea; Bay of Biscay, at great depths. 
Mr. Jeffreys says this species inhabits the Japanese Seas; if 
so, some of the foregoing species will probably refer to it. 
Described and figured by Philippi as P. Renieri, Scacchi—an 
erroneous identification and name changed by Monterosato, as 
above. 
P. Niponica, H. A. Smith. PI. 3, fig. 27. 
Shell light brown, whorls six and a-half, the nucleus large, 
globose, glassy, whorls strongly keeled, and concave above, 
with two or three fine spiral lire; also concave below the carina, 
and encircled on the body-whorl by about ten lirz, becoming 
finer towards the base, the interstices crossed by elevated, 
oblique growth-strix ; slit in the concavity above the principal 
carination; columella a little prominent in the middle and 
oblique below; canal short, scarcely recurved. 
L. 7, diam. 2°5 mill. 
Japan. 
The oblique incremental striz are flexuous and turned to the 
right above the carina, and straight, inclined to the left below it. 
P. triporcaTA, H. A. Smith. Pl. 3, fig. 28. 
Shell pale brown or luteous, the nuclear whorl globular, glassy, 
the rest encircled by distinct keels, of which there are three on 
those of the spire, more numerous on the body-whorl; the inter- 
stices each latticed by three or four revolving lines and incre- 
mental strie; notch deep and wide, above the principal keel. 
L. 14, diam. 4°5 mill. 
Japan. 
