TURBO. 
Puate I. 
Genus TurBo, Linneus. 
Testa turbinata, crassiuscula, interdum umobilicata, intus 
argentea rard aureo-margaritacea, anfractibus plus mi- 
nusve rotundatis, aut rugosis aut glabris, marginibus 
Operculum testaceum, interdum corneum. 
Shell turbinated, rather thick, sometimes umbilicated, 
interior silver, rarely golden-pearly, whorls more or 
disjunctis. 
less rounded, rough or smooth, with the margins 
disjoined. Operculum testaceous, sometimes horny. 
The shells of this genus are remarkable for their beau- 
tiful symmetry of form, and vivid admixture of colours ; 
they are comparatively limited in species and under the 
acknowledged type assigned to them by Lamarck, may be 
readily distinguished from the Monodonte, Trochi and 
others of the turbinate family. 
The Turbines are sometimes smooth, almost porcel- 
lanous, but mostly spirally ribbed or grooved, and their 
variations of sculpture are mainly exhibited m scales or 
lamine. The interior and chief substance of the shell 
consists of pearly nacre often very iridescent, and in one 
or two instances of a golden hue. 
The operculum of the Turbines offers a more curious 
variety of structure than that of any other genus, differing 
occasionally to a remarkable extent in species perfectly 
similar in form and general character, whilst in shells 
of very opposite structure they are frequently the same. 
The same heavy stony operculum which is common to 
Turbo is found also in Trochus, and the horny operculum 
of Trochus is also to be met with in Turbo. It is certain 
that the opercula of the Twrbinacea family furnish no charac- 
ters for generic arrangement, but are well worth observing 
in reference to their specific variation. In most species 
the operculum is of a solid testaceous substance, sometimes 
smooth, sometimes granulous, in others it is deeply cireu- 
larly grooved, the ridges being granulated or serrated, 
then again it is composed of a crowded tuft of club-shaped 
particles. In all these the imner surface is coated with a 
horny layer, and in one or two instances the operculum is 
entirely horny. 
The genus Turbo is far less numerous in species than 
Trochus or Monodonta, and there are not more than two 
or three of small size. They only inhabit warm seas and 
are confined within a much narrower tropical limit than 
others of the family. 
Species 1. (Mus. Cuming.) 
Turpo Navauensis. Turb. testd via imperforald, orbi- 
cular, depressiusculd, anfractibus spiraliter sulcatis, 
suleis regulariter concavis, latiusculis ; olivaceo-viri- 
descente, rufo radiatim maculatd et punctatd, intus 
argented ; operculo testaceo, cristato. 
Tue Nata TurBo. Shell slightly imperforated, orbi- 
cular, somewhat depressed, whorls spirally grooved, 
grooves regularly concave, rather broad ; olive-green, 
radiately blotched and spotted with red, interior 
silver ; operculum testaceous, tufted. 
Hab. Port Natal; Wahlberg. 
The operculum of this beautiful species is a tufted mass 
like that of the 7. sarmaticus. 
Species 2. (Mus. Cuming.) 
TursBo Marmoratus. Turd. testd imperforatd, suborbi- 
culari, ventricosissimd, anfractibus levibus, aut concen- 
tricé striatis, superné depresso-concavis, infra nodis gran- 
dibus tumidiusculis vel carinis bi- triseriatim cinctis ; 
viridi, fusco-rufo alboque marmoratd, intus marga- 
ritaced ; operculo testaceo, crasso. 
THE MARBLED TuRBo. Shell tmperforated, somewhat 
orbicular, very ventricose, whorls smooth or concen- 
trically striated, depressly concave round the upper 
part, encircled beneath with two or three keels or 
rows of nodules; green, marbled with white and red- 
brown, interior pearly ; operculum testaceous, thick. 
Linn £us, Syst. Nat. (12th edit.) p. 1134. 
Eadem. Turbo olearius, Linneeus. 
Hab. Island of Mindanao, Philippines ; Cuming. 
Found in great abundance in the Eastern Seas, and the 
largest of the genus. 
Species 3. (Mus. Cuming.) 
TurBo unpuLatus. Turd. testa orbiculari, late et pro- 
Sundé umbilicaté, anfractibus nune sulcatis, nunc levi- 
bus ; ceruleo-viridi, strigis albis undulatis longitudina- 
liter notatd, intus margaritaced. 
Tue wavep Turso. Shell orbicular, broadly and deeply 
umbilicated, whorls sometimes grooved, sometimes 
smooth; blueish-green, longitudinally marked with 
white zigzag streaks. 
Cummnirz, Conch. Cab. vol. x. pl. 169. f. 1640-1. 
Hab. New Zealand; Earl. 
A species of common occurrence, characterized by an 
unusually large umbilicus. 
January, 1848. 
