HELIX. SNAIL-SHELL. 57 



28. Helix resupinata. Walker, f. 24. 



Shell semitransparent, glossy, horn-color, with the two 

 terminal top spires reversed. 

 At Sandwich : minute. 



29. Helix globosa. Walker, f. 25. 



Shell globular, opakc, white, smooth, glossy, with two 

 volutions : aperture roundish. 

 At Sandwich : minute. 



30. Helix reticulata. Walker, f. 26. 



Shell white, transparent, elegantly reticulate, slightly 

 perforated, with a single volution : aperture rounded and 

 margined. 



At Reculver : minute. 



31. Helix unispiralis. Walker, f. 27. 



Shell white, opake, glossy, concave on both sides, with 

 a single volution : aperture rounded. 

 At Sandwich : minute. 



32. Helix striata. Walker, f. 29. 



Shell transparent, greenish-white, striate : spires three, 

 reflected on the back : aperture somewhat oval. 

 At Sandwich : minute. 



33. Helix coarctata. Walker, i. 30. 



Shell white, transparent, with two volutions : aperture 

 roundish, contracted at the perforation. 

 At Sandwich : minute. 



34. Helix tubulata. Linn. Trans, iii. pi. 13. f. 35, 36. 



Shell longitudinally striate, with three volutions : a mar- 

 gined tube extending beyond the surface of the shell, in 

 the place of a perforation. 



At Pembroke : minute. 



35. Helix fasciata. Linn. Trans, v. pL l.f. 20, 21. 

 Shell whit-e, transparent, slightly perforated, with three 



volutions ; the first tumid, and marked with three belts of 

 a i*ich marone color : aperture dilated. 

 Pembroke. shirs const : minute, 



36. Helix 



