50 TERRESTRIAL AIR-BREATHING MOLLUSKS. 



Uucalodiiim,^ Coelocentrum,^ Lithotis,^ Bhodea, Meyaspira,^ Limicola- 

 7'ia,'^ but ono species has a ribbed jaw, Achatina,^ PseudacJiatina ? Peri- 

 deris? Columna ?'' Bulimus as now constituted has various forms of 

 jaw. 



(6) Jaw with decided stout ribs : Anadenus,^ Avion, Ariolimax, Pro- 

 physaon, Paliifera, Veronicella, Binneya, Hemj^hillia, the genera of dis- 

 integrated Helix,^ Geomotacus,^'^ Letournexia,^^ Peltella,^'^ Xanthonyx,^^ 

 SimpidopsiSy^^ Vfeifferia^'^ Berendtia^^ Carelia^'^ and, as stated above, 

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

 colaria. 



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

 wards the centre : Gteotis,^^ Amphibulima,^^ Buliviulus, Cylindrella, Ma- 

 a'oceramus,^ Pineria,^ Partula.'^ 



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

 piece are Succinea,^^ Omalonyx,"^ Hyalimax^ Athoracophor-us.^ 



C. The genera whose jaw is in separate pieces are Orthaliciis, Liguiis, 

 and Panctum}'^ 



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 nnknown. 



8 Biniiey, Proc. Pliila. Ac. Nat. Sc. 1874, PI. V. Fig. 3. 



* Jaw and dentition unknown. 



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



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



7 Jaw and dentition unknown. 



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



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



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



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

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



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



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



16 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. XL Figs. 1, 5-7. 



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



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



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



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



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



26 Bergh, verb. kais. kcenig. zoolog. botan. Gesell. in Wien., XX. 844, PI. XIL Figs. 



2, 4, 5. 



27 See this work. 



