Rydberg: Notes on Rosaceae 495 



is in A. sericea and A. turbinate. A. gracilipes was first described 

 as a Potentilla. In this respect it has had the same fate as A. 

 turbinate. 



Acomastylis sericea Greene has a more western and northern 

 distribution than A. turbinate (Rydb.) Greene. The following 

 specimens have been seen. 



Nevada: Ruby Mountains, Heller 9139, 9359; East Hum- 

 bolt Mountains, Watson 320; same locality, M. E. Jones 1897. 



Idaho: Salmon River Mountains, Henderson 4035. 



Montana: Indian Creek and Pony, Rydberg & Bessey 4416, 

 4417; Spanish Peaks, Flodman 608; Belt Mountains, Scribner 

 40; Rone Mountain, Chestnut 9. 



Wyoming: Wind River Mountains, V. Bailey; northwestern 

 Wyoming, Rose 290. 



Acomastylis turbinate (Rydb.) Greene. The range of this 

 species covers that of the preceding, but includes also Colorado, 

 Utah, Arizona and New Mexico. 



COWAN I A 



Cowania mexicana D. Don is not found within the United 

 States, and not even near the boundary. It is confined to central 

 Mexico. The plant of southwestern United States and northern 

 Mexico should be known as C. Stansburiana Torr., which differs 

 in the form of the hypanthium and the lobing of the leaves. C. 

 mexicana is represented by the following specimens : 



Mexico: Durango, 1896, Palmer 12, 71; Nelson 4696; Sierra 

 Madre, Seeman; Hartweg. 



Cowania Davidsonii Rydb. is closely related to C. Stansburiana, 

 but differs in the elongated pedicels, the form of the hypanthium, 

 etc. The following specimens belong to it: 



Arizona: Blue River, September 8, 1902, A. Davidson 754; 

 Castle Creek, Bradstran Mountains, 1892, Tourney I29d. 



Cowania alba Goodding is unknown to me, except as to a poor 

 fragment collected by Purpus and as to the descriptions. Purpus' 

 specimens may well represent a hybrid of C. Stansburiana and 

 Kuntzia tridentata. 



Cowania ericaefolia Torr. and C. Howardi S. Wats, are the 

 same. The writer has seen the types of the two, which are 



