148 PROCEEDINGS OF THE ACADEMY OP 



Acavus, Gorilla, Can/odes, Panda, Labyrinthus, CaracollusJ 

 Leucochroa, 2 Cysticopsis P Plagioptycha,* Leptoloma 5 Anostoma, 6 

 AnostomellaP Tomigerus? Boysia? Plectostoma? Hypselosto- 

 ma P Achatinella, 9 Glausilia, 10 Stenogyra, 11 Strophia, 12 Buliminus, 13 

 Balea, u Pupa, 15 Vertigo, 16 Ferussacia, 1 '* Csecilianella, 18 Geostilbia? 

 Azeca ? Tornatella P 9 Zospeum ? 20 Holospira, 21 Euc alodium 22 Coelo- 

 centrum, 23 Lithotis, 24, Phodea, Megaspira 25 Limicolaria, 26 but one 

 species has a ribbed jaw, Achatina, n Pseudachatina ? Perideris ? 

 GolumnaP 8 Bulimus as now constituted has various forms of jaw. 

 (b) Jaw with decided stout ribs : Avion, Ariolimax, Projohy- 

 saon, Pallifera, Veronicella, Binneia, Hemphillia, Helix, 29 Geomo- 

 lacus, ?0 Letournexia, 31 Peltella, 32 Xanthonyx, 33 Simpulopsus,'* Pfeif- 



1 See Semper, 1. c. No doubt other genera of disintegrated Helix will be 

 found to be grouped here. I propose at present to remove from Helix all 

 the species not having ribs upon their jaw. 



2 Bland and Binuey, Ann. Lye. Nat. Hist, of N. Y., X., 220. 



3 Bland and Binney, Ann. Lye. N. H. of N. Y., IX. 



4 Proc. Ac. Nat. Sc. Phila. 1874, 56. 5 Ibid. 58. 



5 Journ. de Conch., XIX., 261, pi. XL, fig. 4. 

 7 Jaw and dentition unknown. 



s Jaw and dentition unknown. 



s Bland and Binney, Ann. Cyc. N. H. of N. Y., X., 335, pi. XV., figs. 

 6, 7. 



10 Troschel, Moquin-Tandon, Lehmann, etc. 



11 See this paper. I2 See this paper. 



13 But some species have ribs. See Moquin-Tandon, Lehmann, etc. 

 11 Moquin-Tandon, Moll. Fi\, pi. XXV., fig. 6. 

 15 See this paper. I6 See this paper. 



17 See this paper. IS See this paper. 



19 Unknown. 



20 Heynemann, Mai. Bl. X., pi. III., fig. 14. Jaw unknown. 



21 See this paper. 



22 See Crosse and Fischer, Journ. de Conch. 1870, pi. V., fig. 1. 



23 Jaw and dentition unknown. 



2 * Binney, Proc. Phila. Ac. Nat. Sc. 1874, pi. V., fig. 3. 



25 Jaw and dentition unknown. 



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



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



28 Jaw and dentition unknown. 29 See this paper. 



o Bland and Binney, Ann. of Lye. of N. H. of N. Y., X., 309, fig. 



31 Bourgignat, Moll. nonv. et lit, VII. 201, pi. XXXIV., fig. 1-7. 



32 Jaw apparently ribbed in Ferussac's figure, pi. VII. A. 



33 Fischer and Crosse, Moll. Mex., pi. IX., figs. 15, 16. 

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



