160 TURBINELLID&. 
callous, spread over the body-whorl, outer lip reflected, not den- 
ticulate or striated. 
In Neritula the last whorl is depressed and extends over the 
penultimate whorl, nearly covering and concealing the spire, 
which consequently appears very obtuse. The animal has a bifid 
tail, and operculum similar to Nassa. H. and A. Adams’ genus 
Teinostoma was originally placed next to Neritula, in their 
“* Genera ;” subsequently they removed it to the Rotellide. 
DesMouLEA, Gray. 
Distr.—6 sp. Senegal, Cape of Good Hope, Japan. D. abbre- 
viata, Wood (lii, 100). 
Shell ovate-globose, covered with a downy epidermis; spire 
short, conical, apex papillary ; whorls depressed; aperture ovate; 
inner lip thickened, with a ridge posteriorly ; outer lip con- 
tracted, thickened externally, plicated internally. Dentition 
unknown. 
Desmoulea is remarkable for its obtuse apex and solid growth, 
much resembling some species of Cassididz ; when in fine con- 
dition, the shell is clothed with a velvety epidermis, but most 
cabinet specimens are denuded of this. The animal is unfortu- 
nately unknown, and therefore the systematic position of the 
genus remains somewhat uncertain—for, whilst some species 
connect closely with Nassa, the revolving sculpture, globose 
form, sunken suture and mouth of others are suggestive of 
Semicassis. 
Famitry TURBINELLID 2. 
This group includes a few ponderous tropical species, allied 
in the characters of the mouth, and in general form and orna- 
mentation, to the Peristerniinz on the one hand, whilst in size 
they approach the Volutidz. The plications on the middle of 
the pillar are rather distant, narrow, high, and transverse, whilst 
in Fasciolariine they are situated lower, are not so prominent, 
and oblique in direction. The epidermis is frequently persistent. 
The animal (of Vasum) is slow-moving, timid and inactive, 
shrinking quickly within the shell on the slightest alarm. The 
operculum is ovate, acute, with an apical nucleus; it is very 
thick, claw-like, and partially free at the hind-part. The denti- 
tion (x, 14) resembles somewhat that of the Buccinide, differing 
in the lateral teeth; it differs widely from the Nasside, and 
quite as much from that of the Fasciolariine or Peristerniine. 
TURBINELLA, Lam. 
Etym.—Diminutive of turbo, a top. 
Syn.—Mazza, Klein. Rapum, Swains. 
