110 LITHIDION. 



1. sulcatiim f«ray> ((^ray Phan. p. 124. — Cy- 



clostomus sulcdtns |Lithidion] Ad. Gen. p. 292. — 



Ct/clost. lithidion Sow.) Mon. p. 176. 



2. desciscens Pfp. (Proc. 1851. p. 243. — Ch. ed. 



nov. p. 262. t. 35. f. 25. 26. — Grny Phan. p. 124. 

 — Cyclostomus dcsciscens [Lithidion] Ad. Gen. 

 p. 292.) - - 177. 



3. Soiileyetianiim Pefi. (Coll. 195. — Ch. ed. nov. 



p. 262. t. 35. f. 23. 24. — Grat/ Phan. p. 124. — 

 Cyclostomtfs Souleyetianus [Lithidion] Ad. Gen. 

 p. 292. — Cyclostoma paradoxum Pfr. olim.) . - - 177. 



4. depresstim Sow. {Ch. ed. nov. p. 261. t. 35. f. 



17 — 19. — Gray Phan. p. 125. — Cyclostomus 



depressus [Lithidion] Ad Gen. p. 292.)' .... - - 178. 



5. nlveiim Pet- (Coll. 196. — Ch. ed. nov. p 261. 



t. 35. f. 20—22. - Gray Phan. p, 125. — Cyclo- 



stomus niveus (Lithidionj Ad. Gen. p. 292.) . . - - 178. 



XXIV. Otopoma Gray. 



Pfr. Mon. Pneuni. p. 179. — Gray Cat. Phan. p. 12G. — 

 Woodward Man. Moll. II. p. 176: subgenus Cyclostomatis. — 

 H. et A. Adams Gen. rec. Moll. II. p. 292 : subgenus Cy- 

 clostomi. 



Conspectus specieruin. 



A. Umbilico prorsus clauso ....§. 1. ISr. 1. 



B. Urabilico magis minusve aperto. 



1. Peristoinatis margine dextro expanso §. 



2. Margine dextro recto §. 



3. Margine dextro flexuoso ....§. 



1. clau8iini ISow. (Gray Phan. p. 126. — Cycloslo- 



mus clausus [Otopoma] Ad. Gen. p. 293.) . . . Mon p. 179. 



§. 2. 



2. aiiriciilare Gray. (Gray Phan. p. 126. — Cy- 



clostomus auricutaris (Otoponia| Ad Geii. p. 292. 



— Cyclostoma candidum Sow J - - 180. 



3. albicaiis Sow- (Gray Phan, p. 127. — Cyclosto- 



mus albicans [Otopoma] Ad. Gcn. p. 292.) . . - - 181. 



4. naticoides Recl. (Coll 197. -- Gray Phan. p. 



127. — Cyclostomus naticoidcs [Otopoma] Ad. Gen. 

 p. 293. — Turbo foliaccus Chemn., Ddlw. Cat. II. 

 p. 866. n. 121?) - - 181. 



