838 CLASS III. GASTEROPODA. ORDER III. CERVICOBRANCHIATA. 
which it establishes between the Capulacea and the Macrostomata, two 
families widely separated by Lamarck. 
The shell of Velutina may be described as being nearly globose, hemi- 
spherical, and covered with a thin epidermis ; the spire is small, obtuse 
and submarginal ; the aperture is very large, rounded, entire, and sharp 
at the edge; the columella is curved, and partially conceals a small um- 
bilicus. 
Examples. 
Pl. CXLVII. Fig. 1 and 2. 
VELUTINA LEVIGATA (2). 
Sigaretus levigatus, Lamarck, Anim. sans vert., vol. vi. 2nd part, p. 208. 
Bulla velutina? Muller. 
Pl. CXLVII. Fig. 3 and 4. 
Vetutina zonata, Gould, Invert. of Massachusets, p. 242. f. 160. 
SIGARETUS, Lamarck. 
Testa suborbicularis, subauriformis, plus minusve depressa, intra pallio 
feré occultata ; spira brevi, partm elevata; apertura dilatata, inte- 
gra, latitudine superante; marginibus superné sejunctis ; impres- 
sionibus muscularibus duabus, lateralibus, subdistantibus. 
Although Adanson was unacquainted with the animal inhabitant of his 
‘« Sigaret,” he made a tolerable guess as to the situation it should occupy 
in the natural system in placing it with the Haliotides. Linnzus was 
less fortunate, for instead of falling into the arrangement of his contem- 
porary, he included it with the Helices (Helix haliotoidea). It must, 
however, be remembered that some authors, especially De Blainville and 
Deshayes, still refuse to allow that any affinity exists between the Siga- 
reti and the Haliotides; for, like the Natice, their shells are almost 
entirely enveloped within the mantle. 
