THE TYPES OF THE LAMARCK COLLECTION IN THE MUSEUM OF GENEVA 985 



designated as the lectotype of M. unifascialis. The spécimen is worn and faded, and 

 has 7 whorls and a worn apex; it is yellowish in colour, ornamented with a 

 double-line white band on whorls; this band is only just discernible on the body 

 whorl. Sculpture consists of rather worn, nodulose axial ribs which number 19 on 

 the body whorl and 18 on the penultimate whorl; the shell is spirally striate, and 

 the siphonal fasciole has ca. 6 strong spiral cords. The aperture is narrow, 4 labral 

 lirae are visible under magnification on the labrum, and the pariétal wall is 

 calloused; the columella has 4 folds. 



The other spécimen No. 1102/81/1: 19.0x8.1 x9.1 mm(Fig. 47 b), isbrownish 

 in colour, and the labrum is smooth; it is specifically excluded as a type to prevent 

 any future misinterpretation. 



Kiener is responsible for the confusion surrounding Lamarck's taxon. In 1838 

 Kiener fîgured on pl. 16, figs. 51, 51, under the name M. unifascialis Lamarck, the 

 species Mitra ( Strigatella) auriculoides Reeve, and on pl. 26, figs. 84, 84, he 

 figured the excluded syntype of M. unifascialis, which is a worn M. coronata; in 

 his " Errata " he gave the name " M. nucleola var. " to the spécimen figured on 

 pl. 26. 



Vexillum ( Costellaria ) unifascialis is a common and highly variable species, 

 which lives throughout the tropical Indo-Pacific région. 



Mitra bacillum Lamarck, 1811 

 (Fig. 48) 



1811. Mitra bacillum Lamarck, Ann. Mus. d'Hist. Nat., 17:219, No. 66 

 1822. Mitra bacillum Lamarck, Anim. s. vert., 7:321 



Habite...; mon cabinet; length 16-20 mm; mss. 1 ex. — Collection Lamarck, 

 Geneva: 1 spécimen. 



Lamarck based his description on one spécimen only, but since this 

 spécimen had a portion of the spire missing, he estimated the probable length 

 of the specirren by giving a size range 16-20 mm. The holotype No 1107/96: 

 16.5 x 6.7 x 10.7mm, is extant in the collection. The spécimen is worn ane faded, 

 also immature, and has only 4 whorls and a portion of the spire missing; it is 

 whitish in colour, ornamented with faded, brown axial streaks, spots at the 

 sutures, and obsolète brown streaks on the spiral cords. Sculpture consists of 

 15 spiral cords on the body whorl and 4 on the penultimate whorl; axial lirae are 

 still faintly visible. The aperture is narrow and elongate, brown and smooth 

 within; the edge of the labial lip is crimped and the columella has 6 white folds. 



Reeve was the first author to misinterpret Lamarck's taxon. Under the name 

 M. bacillum Lamarck, Reeve figured on pl. 16, fig. 117 a species which was later 

 described as Mitra astyagis (Dohrn, 1860). Lamarck's M. bacillum he figured on 

 pl. 16, fig. 120, under the name M.flammea (Quoy & Gaimard). 



