TROCHUS.—Puate IV. 
angustis, concavo-declivibus, sparsim nodoso-granatis, 
deinde angulatis, biseriatim muricato-nodatis; basi con- 
vexo-planatd, tenue sulcata, columella calloso-contortd. 
THE sHARP TRocuts. Shell imperforate, slenderly py- 
ramidal, whitish, stained with greenish-ash; whorls 
narrow, concavely sloping, sparingly nodosely grained, 
then angled, encircled with two rows of prickly no- 
dules; base convexly flattened, finely grooved, colu- 
mella callously twisted. 
Lamarck, Anim. sans vert. vol. ix. p. 141. 
Pyramis acutus, Adams. 
Hab. Philippine Islands; Cuming. 
The most elongately pyramidal and prickly species of 
the genus. 
Species 21. (Mus. Cuming.) 
TROCHUS TRISERIALIS. Tvoch. testd imperforatd, yracili- 
pyramidali, lutescente, viridi vivide variegatd ; anfrac- 
tibus concavo-declivibus, oblique corruyato-striatis, no- 
dulis subdistantibus triseriatim cinctis ; basi convexo- 
pland, densé sulcaté, columella breviter calloso-con- 
tortd. 
THE TRISERIAL Trocuus. Shell imperforate, slenderly 
pyramidal, yellowish, brightly variegated with green ; 
whorls coneavely sloping, obliquely wrinkle-striated, 
encircled with three rows of distant nodules; base 
THE ARCHITECTURAL ‘TROCHUS. 
TROCHUS ARCHITECTONICUS. 
convexly flattened, closely grooved, columella shortly 
callously twisted. 
Lamarck, Anim. sans vert. vol. ix. p. 140. 
Pyramis triserialis, Adams. 
Hab. Philippine Islands; Cuming. 
In this species the sculpture is not of a prickly charac- 
ter, but consists of regular obtuse granular nodules. 
Species 22. (Mus. Cuming.) 
Troch. testé imperforata, 
acute conicd, opaco-albd, pallidé virescentetinctd ; an- 
fractibus concavis, deinde tumidis, undique longitudi- 
naliter plicato-costatis, costis numerosis, interstitiis 
profundé excavatis ; basi convexo-planatd, valide sul- 
catd, columella calloso-contortd. 
Shell imperforate, 
sharply conical, opaque-white, faintly tinged with 
green; whorls concave, then swollen, longitudinally 
plicately ribbed throughout, ribs numerous, inter- 
stices deeply excavated; base convexly flattened, 
strongly grooved, columella callously twisted. 
Pyramis architectonicus, Adams, Pro. Zool. Soc. 1851, 
p- 152. 
Hab. Signet Bay, North Australia; Dring. 
This elegant and very distinct species is remarkable for 
its deeply cut sculpture. 
