100 MADEIRAN SPECIES OP LAURIA. 



lamella. The peristome is brown, thin, expanded and some- 

 what reflected. Length 3.6, diam. 1.5 mm. ; 7% whorls. 



Madeira: chiefly in the north and towards the coast, at 

 rather low elevation, about the roots and dead leaves of 

 Sepervivum tabulajorme and a few other plants which 

 stud the faces of exposed rocks (Wollaston). 



Helix C. sphinctostoma Lowe, Primitive, p. 63. — Pupa 

 sphinctostoma Ppr., Monogr. ii, 335; iii, 543; iv, 569; vi, 

 309. — Lowe, P. Z. S. 1854, p. 209, with var. rupestris and 

 arbor ea. — Albers, Malac. Mader. p. 64. — Wollaston, Test. 

 Atlant, p. 222. 



For comparisons see under L. laevigata and wollastoni. L. 

 sphinctostoma in the wide sense is a highly variable species, 

 the name covering numerous forms and races which can be 

 fully worked out only when sufficient accurately localized 

 material is in hand. 



Lowe distinguished two varieties: "rupestris, the spire 

 more distinctly striate," and " arborea, the shell smoother, 

 more glossy and more obsoletely striatulate. " The first of 

 these is what he had at first figured as sphinctostoma, and 

 the name rupestris is therefore superfluous and yields to 

 sphinctostoma. No definite localities were given for either 

 variety. The figures of sphinctostoma and arborea here 

 given are from specimens out of the Lowe-Wollaston collec- 

 tion, not exactly localized, but serving to fix the identity of 

 the two forms. 



In a specimen from Machico (T. D. A. and W. Cockerell) 

 the striation is finer than typical. Supracolumellar lamella 

 very weak, basal fold minute, tubercular; lower-palatal 

 small. There are no subcolumellar or upper-palatal folds. 



Another specimen, locality unknown, has also very delicate 

 striation and reduced teeth, the supracolumellar and lower- 

 palatal weak, basal, upper-palatal and subcolumellar wanting. 



33ff. Lauria sphinctostoma arborea (Lowe). PI. 11, figs. 

 13 to 16. 

 The shell is more straightly cylindric than L. sphinctos- 

 toma, paler, olive-buff, uniform or banded with brown at 



