1890.] NATURAL SCIENCES OK PHILADELPHIA. 299 



Indies/ and species imported by the agency of man from the United 

 States and Europe.^ In none of the countries named is there, 

 however, a ^ecies of Vaginulus so large, or similar in characters to 

 the one described ; nor have I been able to find any description at 

 all agreeing with the specimens, although I have examined the 

 literature for the Vaginulus species of all countries.'' 

 Helix (Polygyrella) Harfordiana Cooper. PI. V, figs. 12, V.\. 14. 



Dwda/ochila Harfordiana Cooper, Amer. Journ. of Conch., vol. 

 V, pt. 4, p. 196, plate 17, fig. 8. See also tovi. cit., p. 214. 



Heli.v {Dcedalochila) Harfordiana Coop., Tryon, Manual of Con- 

 chology, 2d Series, vol. Ill, p. 130, pi, 27, figs. 55-57. 



Polijgijra Harfordiana Coop., W. G. Binney, Manual of N. A. 

 Land Shells, p. 114, fig. 81, bid not the description! 



Not Triodopsis Harfordiana Cp., W. G. Binney, Terr. Moll. U. 

 S. etc., V, p. 309, fig. 203, 1878. 



This shell has been so much misunderstood and so incorrectly 

 figured that I feel impelled to refigure it and to offer a few sugges- 

 tions concerning the systematic position of the species. It was dis- 

 covered in the year 1869 by Mr. W. G. W. Harford in the " Big 

 Tree " district, Fresno County, California. The locality is an ele- 

 vated one, lying 6500 ft. above the sea level, in lat. 37°. 



In thus devoting space to the consideration of this question of 

 systematic position, I do not Avish to be understood to attach any 

 great importance to those divisions of our Helices which some 

 authors call sections, some siibgenera, and still others designate as 

 full fledged genera. I am fully aware that many of these divisions 

 coalesce ; we can no more trace the separating line between their 

 species than we can unmix mingled milk and water. Thus, the 

 species Texasiana, triodontoides and Levettei bridge the space between 

 Polygyra and Triodopsis ; Mullani, appressa etc., form passages from 

 Triodopsis to Mesodon ; and through germana with its allies on either 

 side, Mesodon flows into Stenotrema. The recognition of the fact 

 that these sections are all varying manifestations of one type, and 



^ Such as Polygyra, Helicina, Succinea, Pupa, the same species of which also 

 inhabit various West Indian Islands. 



- Helix ventrosa, Stenogyra decollata from Europe ; Helix appressa from 

 the United States; the last is not abundant in Bermuda and the colony may not 

 be a permanent one. 



3 The principal works are Fisher's Monograph of the genus in Nouv. Arch, 

 du Mus., VII, 1871, Heynemann's valuable articles in Jahrbiicher Deutsch. 

 Malak. Ges. XII, 1885, and Semper's beautiful work on the Philippine Island 

 fauna. 



