LAUEIA, AZORES ISLANDS. 125 



emerges further; the lower palatal fold is well developed but 

 often hard to see on its light background. Basal fold is 

 variable in size. Figures are from specimens received from 

 Morel et. 



Morelet has called attention to the radial lamina' within 

 the base of young shells. In one of 3 1 ,o whorls there is a 

 lamella on the parietal wall, one on the columella, and two 

 radial lamina 1 in the base at intervals of % whorl. A nearly 

 adult shell has three such lamiiue, and there is one lamina in 

 a specimen with well formed lip and teeth. Morelet states 

 that the young are hardly distinguishable from those of L. 

 fasciolata. 



L. fuscidula, being reported from "tout l'Arehipel" is 

 evidently a wide-spread species which may be expected to 

 show racial differentiation on the several islands. Several 

 forms are present in the series (four lots) examined, but 

 only two lots are definitely localized. 



The original account of L. fuscidida states that there is one 

 lamella columcllaris. This is the case in some examples, such 

 as pi. 15, fig. 6, which must therefore be considered .the 

 typical form. In some other shells of the same lot, received 

 from Morelet, there is a low and very deeply immersed supra- 

 columellar prominence visible only in an oblique view in the 

 mouth. Whether these forms were associated in life re- 

 mains uncertain; also, the island is not stated on the label. 



Form hexodon, n. f. PI. 15, figs. 9, 10, 11. The supraeolu- 

 mellar lamella is well developed and visible in a direct front 

 view. 



Length 2.5, diam. 1.35 mm. ; 6 whorls. Fig. 9, type. 



Length 2.3, diam. 1.5 mm. ; 5% whorls. Fig. 10. 



San Miguel. The type lot, No. 22867, was received from 

 Morelet. 



Another form in the collection, represented by a single 

 specimen without record of the island, is very pale, showing 

 scarcely any trace of the brown band. It lacks supracolu- 

 mellar lamella and basal fold, and the parietal lamella is 

 only about half as high as the angular. Probably this re- 

 presents another race. 



