THE NAUTILUS. 135 



It is a long time since I paid particular attention to these small 

 snails, but I do not think the above can be correct. 



The genuine V. coloradenais is a very small form, with only a 

 single lamella on the parietal wall; its length is 1J mm. The form 

 which I named concinnula I found at higher elevations; it is larger, 

 2 mm. long, cylindrical, dull brown with whitish strire, whorls 4J, 

 striate, suture not very deep, mouth pyriform, usually elbowed ex- 

 ternally above, lamellre 4 or 5 ; one, double, on parietal wall ; one 

 on columella, about its middle, and two on outer wall ; peristome 

 distinct. This differs from decora in color and the shape of the 

 aperture. 



I did not publish a description of my concinnula, because I be- 

 lieved (and still believe) it to be identical with Ancey's ingersolli, 

 which, also unpublished, had priority in MS. But, in view of Mr. 

 Dall's publication, it becomes necessary to refer to it and explain 

 what it really is. 



Now as to ingersolli, it was based on Ingersoll's supposed califor- 

 nica. Mr. J. H. Thomson sent me some of the " calif o mica" col- 

 lected by Ingersoll, and I transcribe my notes upon them : 



No. 6. "Aniruas Valley, Colo." and "Timber Line, N. E. Ante- 

 lope Pk., V. californica Rowell." (Perhaps only the latter label 

 really belongs to the shells.) Certainly not californica, but appar- 

 ently concinnula. 



No. 7. " Vertigo californica Rowell, Rio La Plata, Colo." Rather 

 highly colored, but evidently concinnula. 



No. 8. "V. californica, Cunningham Gulch." Shinier than usual, 

 perhaps, or thinner, but concinnula. 



There was also a single specimen of the same species from North 

 Park, collected by E. A. Barber, Aug. 12, 1874. 



Typical V. decora is 2j mm. long, therefore much larger than 

 coloradensis. It is to me evident that there are three quite distinct 

 forms: (1) True decora of the north ; (2) ingersolli or concinnula of 

 high elevations in Colorado ; (3) coloradensis of the Colorado mid- 

 alpine. Whether these are called species or subspecies is, perhaps, 

 of small importance, and Dr. Sterki may be allowed to decide. 



I may later refer to some other matters in Dr. Dall's excellent 

 paper. He keeps " Limax montanus " as a species, which it certainly 

 is not. The Patula strigosa v. concentrata Dall, seems to be a form 

 similar to my var. minor (J. of Conch., 1890, p. 175), which forms a 

 distinct race near Egeria, Colorado. 



