136 THE NAUTILUS. 



more careful view will increase to thousands the numbers which may 

 be seen under favorable conditions. Several pairs were observed in 

 the act of copulation in fact, this was a very common thing on this 

 visit." 



Mr. Dakan found another colony of gabbiana at Newcastle, where 

 he collected over a thousand live ones in twenty minutes. Since then 

 I have collected all along the Grand Hogback from Newcastle to 

 Meeker and north to Axial, up White River to Trapper's Lake and 

 Marne Lakes, in North Park and Middle Park, and everywhere 

 under favorable conditions have found the shells of this genus in 

 great abundance, each species usually occupying a colony by itself, 

 though in some instances they intermingled. While scattering ones 

 are found elsewhere, they are abundant only on slopes or ledges of 

 limestones or calcareous soils or shales, where there are bushes of 

 various kinds. They are found indifferently under sage brush, wild 

 rose bushes, mountain mahogany, Amelanchier and many other 

 bushes, but are not often abundant under aspens or oaks, in this re- 

 spect differing from the smaller species of snails. Loamy, willow- 

 covered bottom-lands do not appeal to them. Where they occur in 

 numbers they are easily found alive on moist days, when it is raining 

 or the bushes are dripping with fog or dew. I have seldom found 

 other snails common where Oreohelix are abundant. 



Without attempting to enumerate all the localities from which a 

 few specimens have been collected, I give below a summary of the 

 more important colonies and some other records to show the general 

 distribution of the species, the collector's name being given except 

 where I conducted the material myself, these records being all based 

 upon material in the University of Colorado Museum. 



OREOHELIX STRIGOSA DEPRESSA Ckll. 



To this form I have assigned all our Colorado material formerly 

 considered strigosa. Present but not abundant usually along the 

 eastern foothills of the Front Range from Pueblo to Belleview. 

 The finest specimens we have are a few from an altitude of 11,000 

 feet on Mt. Audubon (A. Mackenzie, 1905), one very strigose spec- 

 imen from near Ohio City, at 11.800 feet (Frank Rohwer). A few 

 are from Treasury Mountain, Gunnison county, at 10,900 feet (Prof. 

 R. D. George). The highest record is from 14 miles west of Lead- 

 ville, at 12,700 feet (H. A. Aurand). Binney and Cockerell have 



