132 CATALOGUE OF PHANEROPNEUMONA. 
mellar margin vaulted and reflected, almost closing the per- 
forated axis. Height 14, greatest breadth 17, least br. 133 
mill. 
Cyclostoma multilineata, Jay, Catal. 1839, p. 123, t. 7, f. 12, 13. 
Cyclostoma flexilabrum, Sow. Thes. un. 112, p. 130, t. 31, f. 258, 259 ; 
Pfr. Ic. n. 87, p. 91, t. 11, f. 7, 8; Say, Catal. 1850, p. 256, 
n. 5869. 
Cyclostoma flavilabre, Petit, in Journ. Conch. 1850, i. p. 42. 
Trophidophora flexilabrum, Gray, Cat. Cycl. p. 41, n. 15. 
Otopoma multilineatum, Pfr. Consp. n. 274; Pneum. Mon. p. 187. 
Hab. Madagascar (Powis). 
XXI. CYCLOSTOMUS. 
Operculum rather ovate, shelly, flat; whorls 4-5, gradually in- 
creasing, with simple margins; nucleus excentric. Shell de- 
pressed, globose-turbinate or ovate-turreted. Aperture ovate. 
Peristome simple, straight or expanded, often double. 
Cyclostomus, Montfort, Conch. Syst. 11. p. 286; Gray, in Proc. Z. 8. 
1847, p. 181, n. 514; Pfr. in Z. f. M1851, p. 159; Consp. p. 31; 
Pneum. Mon. p. 188. 
Cyclostomus et Tropidophora, Gray, Cat. Cycl. p. 42, 37. 
Tropidophora, T’roschel, in Z. f. M. 1847, p. 44. 
Tropidophora et Cyclostoma (part), Pfr. in Z. f. Mf. 1847, p. 106, 
Ty. 
Cyclostoma sp., Lam. et Auctt. 
A. Keeled. 
1. Depressed : 
2. Turbinate-conical. 
a. With two or more keels . 
6. With a single keel 
B. Not keeled. 
1. Depressed ‘ ‘ 
2. Globose-turbinate. 
a. Peristome reflected. 
Or Onn mm 
bo 
ie 
bo 
> 
4... 90 ee 
a. Broad 5. 4, dl-37. 
B. Narrow 6. ,, 38-54. 
6. Peristome straight 7. 4 55-59. 
3. Ovate-turreted. 
a. Peristome straight . : 
b. Peristome expanded, double. 
a. Smooth . . . 
B. Folded longitudinally 
y. Decussated : 
OnOKnKO? wm OvOrn07 
