22 
Helix Michaudi Pfeiffer Monogr. I. p. 157. n. 406. 
— in Chemn. II. Hei. pars 1. p. 257. n. 238. t. 38. fig. 27 — 29. 
Reeve Conch. icon. Hei. 1. 138. fig. 873. 
— bicolor Lowe Primit. p. 58. n. 52. t. 6. fig. 22. 
Habilat in Portosancto, in cacumine montis „Pico de Facho.” Rara. 
Sectio Crenea *) 
Testa aperte vel obtecte umbilicata vel perforata, formam coni depressi, rarius 
elati exhibens; anfractus 5 — 10 planiusculi, saepe exserti, ultimus carina crenulata vel 
margine acuto, interdum demum evanescente cinctus; apertura lunaris, angulata, saepe 
securiformis, margo columellaris callosus, plus minusve reflexus, appressus. 
10. Helix Wollastoni Lowe. 
Tab. 4. Fig. 1 — 3. 
Testa imperforata, depressa, solida, oblique et valide undato -plicata, badia, inter- 
dum dilute bifasciata; spira parum elevata, apice acutiuscula, sanguinea; sutura impressa; 
anfractus 5 plani, ultimus acute carinatus, antice profunde descendens, basi modice con- 
vexus; apertura perobliqua, subrhombea, intus nitida, callo tenui roseo obducta; peristoma 
simplex, marginibus callo crassiusculo roseo junctis, supero recto, basali dilatato, plano, 
incrassato. , 
Diam. maj. 20, min. 16, ait. 9^ millim. 
Helix Wollastoni Lowe Synops. p. 9. n. 41. 
— — Pfeiffer Monogr. III. p. 169. n. 904. 
— — — in Chemn. H. t. 152. fig. 15 — 16. 
— — Reeve Conch. icon. 1. 136. fig. 853. 
Habitat in Portosancto. Rara. 
Hei. scabriusculae Desh. proxima, differt colore, testa undato - plicata, omnino im- 
perforata, anfractibus non exsertis, margine peristomatis basali stricto nec reflexo. 
11. Helix tectiformis Sowerhy, 
Tab. 4. Fig. 4 — 8. 
Testa umbilicata, depresse semiglobosa, calcarea, superne leviter striata, basi con- 
fertim et aequaliter granulata; spira brevis obtusa; anfractus 7 planati, lente accrescentes, 
ultimus acute carinatus, carina late deflexa, tectiformis; apertura perobliqua, rotundato- 
Albers Heliceen p. 77. 
