Ryuberg : Rocky Mountain flora 57 



RHAMNACEAE 



Rhamnus betulaefolia Greene is to be added to the flora; it was 

 collected in southeastern Utah in the summer of 191 1 by Professor 

 Garrett and myself. 



MALVACEAE 



Dr. Greene* in segregating Eremalche from Malvastrum made 

 this statement: "and that there exists so much as one real Mal- 

 vastrum north of the Mexican border, I hold to be doubtful." 



A little investigation in the history of the genus would show 

 that this statement is untenable. It is evident that Dr. Gray did 

 not base his conception of the genus Malvastrum on the section 

 Malvastrum of Malva of De Candolle, for this section contains 

 the typical species of Malva also. 



The first subsection of this section of De Candolle's is Chry- 

 santhae, and some species of this subsection must be regarded as 

 the type of Malva section Malvastrum DC. Of this subsection Dr. 

 Gray remarked: "If the yellow flowered species with a somewhat 

 different habit and usually a manifest persistent involucre, which 

 forms a second section (the Chrysanthae DC, etc.), are correctly 

 referred to this genus, it will comprise a large number of species 

 from tropical and South America, which need an elaborate revision. 

 I enumerate below merely the North American species which are 

 known to me." Furthermore, Dr. Gray did not include in his 

 genus a single species of Malva given by De Candolle. This 

 shows that Dr. Gray based his genus on the North American 

 species and in publishing the genus he gave the name as "Mal- 

 vastrum Nov. Gen."' without citing De Candolle's section, al- 

 though he had referred to it a few pages before in a footnote under 

 Callirrhoe. As the type of the genus Malvastrum, therefore, we 

 must desigate the first given binomial under Malvastrum, which is 

 M. coccineum. Of the other species included in the original publi- 

 cation M. Fremontii Torr., M. Wrightii A. Gray, M. grossulariae- 

 folium (Hook.) A. Gray, M. angustum A. Gray, M. Munroanum 

 (Dougl.) Gray, and M. spicatum (L.) Gray are plants of the 

 United States. I agree with Dr. Greene that M. rotundifolium 

 A. Gray and M. exile A. Gray should not be included in Malvas- 



* Leaflets 1 : 207. 1906. 



