356 PROCEEDINGS OF THE ACADEMY OF [May, 



unexplored country, our present conclusions must be mere approxi- 

 mations to the facts, which future exploration may be expected to 

 bring out. In treating of forms which are in doubt it seems to me 

 better to attach them as subspecies to a known species, rather than 

 to increase the number of ill-defined species. Oreohelices sometimes 

 have strongly marked conchological features, but when this is not 

 the case, species should not be established in my opinion, without 

 anatomical examination. It seems likely that some forms now 

 considered subspecies of 0. strigosa will be elevated to specific rank 

 when their areas are well explored, and their soft anatomy worked out. 



The "forms" of the list above are of unequal value, but all are 

 inserted in order that all names proposed may appear in the list. 

 Some of them are mere synonyms; some are color or size forms, 

 from heterogeneous colonies, in which several mutations are per- 

 petuated in hybrid populations, 6 such as I have described in Achati- 

 nella. 6 Others are races probably deserving recognition in nomen- 

 clature. Much more study must be put on Oreohelix before we can 

 confidently assign all the forms to their approximately proper rank. 



0. cooperi (W. G. B.). No serious study of the races and forms 

 of this wide-spread species has recently been made. Many years 

 ago Professor Cockerell proposed several varietal names, but in the 

 absence of figures, the application of some of them, as well as their 

 status, has been uncertain. A recent communication from Professor 

 Cockerell quoted below, elucidates them so far as possible in the 

 present condition of the subject. 



(1) typica = 0. cooperi s. str. 



(2) confluens. (3) trifasciata. Color (band) variations of cooperi, common and 



well known to us here. Not in any sense special races. Type specimen of 

 confluens is in U. S. N. M. 



(4) elevata. A form of cooperi with more elevated spire. Merely an extreme 



of the ordinary variation of the species; riot a race. 



(5) minor. The name was originally given in Nautilus May, 1889, p. 8, and 

 referred to a small form cited by Hemphill. Later I found what I considered 

 to be the same in Colorado, apparently a distinct race. Henderson has used 

 the name for a race in recent years. Now we are both uncertain whether 

 the name should be applied in this sense. It is a fact that in certain localities 

 the shells are small and constitute a "minor" race, but whether all the 

 various colonies of this type have any connection with one another may be 

 questioned. The original intention was to follow the European custom, 

 and call all the shells below a certain size minor, not regarding the variety 

 as a race or subspecies in any sense. Henderson and I, after consultation, 

 agree that the status of minor must be considered subject to revision. 



(6) globosula. This we have, and can recognize it as a peculiar variation which 

 occurs in the Glenwood Springs district. It occurs in small numbers on the 

 south side of the river, along with the other forms. It may be a hybrid of 



5 See the valuable observations of Daniels. Nautilus XXV, 1911, p. 18. 



6 Manual of Conchology, Vol. XXII. 



