MADEIRAN GROUP. 77 



Vitrina Lamarckii, Lowe, (pars), Cambr. Phil. Soc. Trans. 



iv. 40. t. 5. f. 1. a. (1831 } 



nitida, Gould, Proc. Post. Soc. N. H. ii. 180 (1848) 

 Lamarckii, Lowe, Proc. Zool. Soc. Lond. 164 



(1854) 



nitida, Alb., Mai. Mad. 15. t. 2. f. 1 -3 (18*4) 

 Lamarcki, Paiva, Mon. Moll. Mad. 8 (1867) 

 nitida, Pfeiff., Mon. Hel. vii. 21 (1876) 



Habitat Maderam ; in sylvaticis intermediis vulgaris. 



This is the universal Vitrina of Madeira proper, where it is 

 more or less abundant throughout most parts of the sylvan dis- 

 tricts at intermediate and lofty altitudes, occurring, like the 

 preceding two, beneath damp stones and refuse, on the mossy 

 trunks of trees, and under logs of decaying wood. But I am 

 not aware that it has been observed for certain elsewhere in the 

 Group ; for although it is true that Mr. Lowe recorded it origi- 

 nally as existing in Porto Santo likewise, he had not at that 

 time distinguished more than a single Vitrina as inhabiting 

 the archipelago, and it was not until 1854 that he separated as 

 specifically distinct (under the name of media) the previously 

 described V. marcida, of Grould, which is not only common in 

 Porto Santo, but which may almost be denned as principally 

 Porto-Santan ; and as for the Baron Paiva's assertion that it is 

 to be found on the mountains of that island, as well as on the 

 adjacent rock known as the Ilheo da Fonte d'Areia, it must be 

 taken for what it is worth, seeing that, by his own admission, 

 he could not himself discriminate the two species in question. 1 

 So that I think we must still require evidence of a more posi- 

 tive nature before it will be safe to cite the V. nitida as occur- 

 ring beyond the limits of Madeira proper. 



The present Vitrina is, on the average, a trifle smaller, and 

 just appreciably more brilliant and highly coloured, than the 

 ruivensis ; and it is also less depressed (or more ventricose and 

 Heliciform), and, instead of there being only two, there are 

 about 3J or even 4 volutions. The spire too is less flattened, 

 the nucleus (which is generally paler, and subcentral instead of 

 lateral) being somewhat convex, and the suture is consequently 

 deeper and more conspicuous. The aperture is both less enor- 

 mous and rounder (causing the left-hand portion of the ultimate 

 whorl, when viewed from beneath, to be relatively wider and 

 more visible) ; and the surface appears to be almost free (even 

 under a high magnifying power) from any traces of the minute 



1 That this was the case, it appears evident from his remark under the 

 V. marvida : ' Species mihi dubia, nee a corigeneribus sat distincta.' 



