THE TYPES OF THE LAMARCK COLLECTION IN THE MUSEUM OF GENE VA 987 



The spécimen No. 1 108/15:12.7 X 8.6 x 7.5 mm, is designated as the lectotype of 

 M. pisoîina. The spécimen is rather worn and faded, and has 5 whorls and a worn 

 apex; it is yellowish in colour, ornamented with moderately large, blackish-brown 

 rhomboidal spots at the sutures and the base. Sculpture consists of ca. 1 1 coarse, 

 arcuate and somewhat obsolète axial ribs on the body whorl and penultimate 

 whorl; the shell is spirally finely striate and the siphonal fasciole has 4 nodulose 

 spiral cords. The aperture is moderately narrow, the labial lip is thick, the pariétal 

 wall has a prominent callus and the columella has 3 prominent folds, of which 

 the posterior one is the largest. 



Lamarck also described a var. b, which differed mainly in colour, being 

 orange with white maculations; this variety was obviously based on a faded 

 example. This spécimen, which was said to measure 7 lig. = 15.8 mm (1822), is not 

 among the 5 spécimens in the collection. 



Pusia pisoîina (Lamarck) is an uncommon species which appears to be 

 restricted to the East Indian Océan — West Pacific région. 



Mitra dermestina Lamarck, 1811 

 (Fig. 51) 



1811. Mitra dermestina Lamarck, Ann. Mus. d'Hist. Nat., 17:221, No. 76 

 1822. Mitra dermestina Lamarck, Anim. s. vert., 7:323 

 L'Océan des grandes Indes (error!); mon cabinet; length 14 ou 15 mm; mss. 

 5 ex. — Collection Lamarck, Geneva: 5 spécimens. 



Dimensions 



Length 



Width 



Height of 

 Aperture 



Lectotype No. 1102/82/1 (Fig. 51) 



14.5 



8.0 



8.0 



Paralectotype No. 1102/82/2 



16.0 



8.0 



9.0 



Paralectotype No. 1102/82/3 



12.7 



6.6 



6.9 



Ail 5 spécimens of M. dermestina are extant in the collection; besides the 3 

 spécimens designated as lectotype and paralectotypes, the other two spécimens 

 measure 10.3 and 7.6 mm in length. The lectotype has 6 whorls and a missing 

 protoconch; it is whitish in colour, ornamented with 3 dark brown transverse 

 bands on the body whorl and a single band at the sutures on earlier whorls ; in 

 addition, orange transverse zones are faintly visible. Sculpture consists of 17 axial 

 ribs on the body whorl and 16 on the penultimate whorl; interstices have deep 

 spiral grooves, and the siphonal fasciole has 4 granulose cords. The aperture is 

 narrow, lirate within, the labial lip is angulate and the pariétal wall has a white 

 callosity; the columella has 4 folds. 



Rev. Suisse de Zool., T. 76, 1969. 



65 



