12 



It is thought best to include a considerable fragment of the very in- 

 volved synonymy of this species because agreement is far from general as 

 to the correct name and for lack of the essential literature the author is not 

 in a position to form an intelligent opinion of his own. The name hammonis 

 is chosen chiefly in deference to the authority of Pilsbry and Vanatta. 

 The generic name is that adopted by Gude and Woodward, the most recent 

 writers on the subject. 



The Kananaskis specimens are rather small for the species. The 

 Waterton Lake specimen is somewhat reminiscent of P. binneyana, which 

 has been found nearby in Montana, but has the narrower umbilicus of 

 hammonis. 



Zonitoides arborea (Say 1817) 



1817. Helix arboreus Sav, Nicholson's Encycl., 1st Am. Ed., pi. 4, 



f. 4. 



1841. Helix arborea Gould, Inv. Mass., p. 182, f. 110. 

 1864. Helix breweri Newcomb, Proc. Cal. Acad. Nat. Sci., vol.. 3, p. 118. 

 1864. Hyalina arborea Morse, Jour. Portl. Soc. Nat. Hist., vol. 1, p. 14, 



text f. 28, pi. 6, f. 29. 

 1869. Hyalina arborea Binney and Bland, Land and Freshwater Sh. 



N. Am., I, p. 33, f. 38-40. 



1885. Zonites arboreus Binney, Man. Am. Landsh., pp. 19, 23, 30, 31,32, 



35, 57, 61, 65, 179, 201, 202, 203, 356, 388, 478, f. 13-14, 211, 214. 



1893. Hyalina arborea Taylor, Nautilus, vol. 7, p. 86 (recorded from 



Laggan, Alberta). 



1898. Zonitoides arboreus Pilsbry, Nautilus, vol. 11, p. 131 (merely 



catalogued) . 



1905. Zonitoides arboreus Ball, -Land and Freshwater Moll. Alaska, 



pp. 8, 14, 42. 



1906. Zonitoides arborea Vanatta, Nautilus, vol. 20, p. 95 (recorded 



from Field, B.C.). 



1906. Zonitoides arborea Walker, Moll. Mich., I, pp. 483, 484, f.55, 56, 58 

 (after Binney). 



Material Examined ** 



Petasina fulva alaskensis (Pilsbry 1899) 



1885. Zonifes (Conulus) fulvus Binney (pars), Man. Am. Landsh., pp. 20, 



23, 25, 27, 28, 32, 36, 57, 67, 201, 203, 354, 479. 



1893. Conulus fulvus Taylor, Nautilus, vol. 7, p. 86 (recorded from 

 Laggan, Alberta). 



