50 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



Eucalodium, 1 Ccelocentrum, 2 Litkotis, 5 Rhodea, Megaspira,* Limicola- 

 ria, 5 but one species has a ribbed jaw, Achatina, 6 Pseudachatina ? Peri- 

 deris ? Columna ?"* Bulimus as now constituted has various forms of 

 jaw. 



(6) Jaw with decided stout ribs : Anadenus, 8 Arion, Ariolimax, Pro- 

 pliysaon, Pallifera, Veronicella, Binneya, ffemphillia, the genera of dis- 

 integrated Helix, 9 Geomolacus, 10 Letournexia, 11 Peltella, 12 Xantkonyx 

 Simpulopsis, 1 * Pfeijferia, 15 Berendtia, 16 Carelia, 1 " 1 and, as stated above, 

 some species now included in Bulimus, Cochlostyla, Buliminus, Limi- 

 colaria. 



(c) Jaw with separate, delicate ribs, usually running obliquely to- 

 wards the centre : Gceotis, 18 Amphibulima, 19 Bulimidus, Cylindrella, Ma- 

 croceramus, 20 Pineria, 21 Partula. 2 ' 2 



B. The genera whose jaw is in one piece with an accessory quadrate 

 piece are $ucciitea, zs Omalonyx 2 * Hyalimax,^ Athoracophorus. 26 



0. The genera whose jaw is in separate pieces are Orthalicus, Liguus, 

 and Punctum. yi 



I have arranged the American genera in the same manner in the 

 follow ng pages. 



1 See Crosse and Fischer, Journ. de Conch., 1870, PI. V. Fig. 1. 



2 Jaw and dentition unknown. 



8 Binney, Proc. Phila. Ac. Nat. Sc. 1874, PI. V. Fig. 3. 



4 Jaw and dentition unknown. 



6 Bland and Biuney, Amer. Jour. Conch., VII. 181. 



6 Von Martens, ed. 2, p. 201. 



' Jaw and dentition unknown. 



8 Heynemann, Malak. Blatt., X. 138, PI. I. Fig. 1. 9 See this work. 



10 Bland and Binney, Ann. of Lye. of N. H. of N. Y., X. 309, Fig. 



11 Bonrgignat, Moll. nouv. et lit., VII. 201, PI. XXXIV. Figs. 1-7. 



12 Jaw apparently ribbed in Ferussac's figure, PI. VII. A. 



13 Fischer and Crosse, Moll. Mex., PI. IX. Figs. 15, 16. 

 " Shuttleworth, Diag., No. 6, p. 147. 



15 Morch, Journ. de Conch., 1865, 385. 



is Crosse and Fischer, Journ. de Conch., 1870, PI. V. Figs. 11, 12. 



17 Binney, Pr. Phila. Acad. Nat. Sc. 1876, p. 185. 



18 Bland and Binney, Ann. Lye. N. H. of N. Y., Vol. X. PI. XI. Figs. 1, 5-7. 



19 Proc. Phila. Ac. N. Sc. 1874, PL VIII. Figs. 2, 5, 6. Pellicula is a synonyme of this. 

 2 See this work. 21 Bland and Binney, Ann. N. Y. Lye. N. H., X. 22. 



22 Binney, Ann. Lye. N. H. of N. Y., XL 45. 



23 See this work. 24 Malak. Blatt., X. PI. IV. Fig. 5, a. 

 25 Fischer and Crosse, Journ. de Conch., XV. 218, PI. X. Figs. 5, 7. 



2 Bergh, verh. kais. koeuig. zoolog. botan. Gesell. in Wien., XX. 844, PI. XII. Figs. 



2, 4, 5. 

 27 See this work. 



