MADEIRAN GROUP. 99 



merges entirely into the suture at the commencement of the 

 penultimate whorl (instead of being minutely raised above it, 

 and so more or less faintly traceable up the spire), its umbilicus 

 is always completely closed over, its peristome has the two lips 

 more evidently connected by a corneous callosity, and the 

 portion towards the axis internally broader, and its surface is not 

 only more opake and granulated but totally different in hue, — 

 being dark and often obscurely banded, instead of nearly 

 white. 



I possess eight examples of the H. Wollastoni which are so 

 nearly intermediate between that species and the phlebophora (!) 

 that it is almost impossible to tell at first sight, to which of the 

 two they should be assigned. They are smaller and less granu- 

 lated than the ordinary type, and very much less distinctly 

 keeled ; and I may perhaps cite them as the ' var. a. subdubia.' 



Helix forensis, n. sp. 



T. omnino imperforata, subdiscoidea, utrinque convexius- 

 cula, mediocarinata, opaca, ubique densissime granulata plicisque 

 valde obliquis remotis subundulatis subirregolaribus instructa, 

 supra subinaequaliter vel marmoratim rufo-brunnea nucleo 

 (Iseviore, prominente) subroseo, sed subtus in medio {i.e. intus 

 fasciam latam marginalem) pallidior aut magis flavescens ; 

 anfractibus 5^ planiusculis, ultimo antice valde descendente, 

 sutura distinctissima, impressa ; apertura valde obliqua, labris 

 couniventibus, lamina callosa, incrassata, albida (intus rosea) 

 juuctis ; peristomate roseo, basi reflexiusculo, axin versus 

 incrassato et ibidem dilatato-plano. — Diam. iniaj. 9 lin. ; 

 alt. 4i. 



Helix Wollastoni, Alb., Med. Mad. t. 4. f. 1-3 \nec diagn.] 

 (1854) 



Habitat ins. parvam 'Ilheo de Fora' dictam, juxta Portum 

 Sanctum [nee Ilheo de Fora juxta Maderam, ; nee etiam in 

 Portu Sancto ipsissimo] ; a DD. Leacock et Moniz olim com- 

 municata. 



Obs. — H. Wollastoni affinis, sed nisi fallor vere distincta. 

 DifFert testa minore, densius rugosiusque granulata (quare 

 omnino opaca), necnon obscurius colorata, — sc. submarmoratim 

 rufo-brunnea (nucleo magis prominulo, Iseviore, roseo), nee 

 supra etiam obscure fasciata, subtus in medio solum pallidiore, 

 fascia exteriore usque ad carinam ipsam extendente ; apertura 

 paululum magis rotundata (aut subminus carinatim angulata), 

 labris callo crassiore junctis. 



Several examples of this shell (which Albers appears to have 

 figured as the H. Wollastoni, Lowe, whilst drawing out his 



H 2 



