HELIX §. 20. 21. 107 



apertura parvula , subverticalis , lunato-subcircularis ; perist. sim- 

 plex, acutum. — Diam. maj. 2 '/2, min, 2'/», alt. 1 y^ mill. (Mus. 

 Cuming. ) 



Helix arctispira Pfr. in Proc. Zool. Soc. i846. p. 41. 

 Habitat in insula Juan Fernandez , una cum H. tessellata. 



Obs. Characleribus intermedia inter H. costellalam et tessellatam, ab 

 utraque spira convexiuscula etc. valde diversa. 



269. H. tenuicostata Shuttleworth. 



T. umbilicata, depressa, tenuis, tenuiter costulata, cornea; 

 spira convexiuscula , obtusa ; anfr. 4 convexiusculi, ultimus antice 

 non descendens, basi sublaevigatus; umbilicus latiusculus, per- 

 spectivus; apertura subobliqua, lunato-circularis; perist. simplex, 

 acutum, margine columellari vix dilatato. — Diam. maj. 2^3, 

 min. 2^4, alt. 1 /3 mill. (Mus. Cuming.) 

 Helix tenuicostata ShuttL in sched. Cuming. 

 _ _ pfr. Symb. IH. p. 68. 



Habitat in Sardinia. 



Obs. Nescio, an haec species ab auctore rite descripta sit? In hoc casu 

 H. lenuicostala Dkr. (Nr. 880.) alio nomine designanda erit, in contrario spe- 

 cies Shutlleworlhiana. 



§. 21. 

 270. H. euryomphala Pfr. 



T. umbilicata, orbiculato-convexa, tenuis, pellucida, virenti- 

 cornea, superne regulariter costulato-striata , lineis concentricis 

 obsolete decussata, basi distantius striata, nitidissima; spira 

 parum elevata , obtusa ; anfr. 6 convexiusculi , ultimus dilatatus, 

 subdepressus, antice nondescendens; umbilicus magnus, pervius; 

 apertura oblique lunato-ovalis, intus margaritacea; perist. rectum, 

 simplex , marginibus conniventibus. — Diam. maj. 37 , min. 32, 

 alt. 17 mill. (Mus. Cuming.) 



Helix euryomphala Pfr. in Proc. Zool. Soc. 1845. p. 71. 

 Habitat in insul» Cuba. 



271. H. Walkeri (Zonites) Gray. f 



T. depressa, umbilicata, polita, flavo-brunnea ; anfr, 3 '/2 ci- 

 tissime majores, ventricosi, tenuiter concentrice striati, dorso 

 striis densis spiralibus; umbilicus profundus; apertura magna; 

 faux albida. — Diam. 1 unc, , axis 8 lin. (Gr.) 



Zonites Walkeri Gray in Proc, Zool. Soc. 1834. p. 63. 



— — 3tiill. synops. p. 13. 



Mesomphix Walkeri Beck ind. p. 7. 

 Habitat in Nova HoIIandia, 



