SUPPLEMENT TO THE FLORA OF MONTANA. 87 



Acer glabrum tripartitum, Pax. ; Rydberg, Flora, 270. Whatever 

 may be the validity of this variety elsewhere, its occurrence in Mon- 

 tana is doubtful, though the young shoots of A. glabrum are not 

 rarely trifoliate, and occasionally there is a similar tendency in the 

 foliage of the whole shrub, such sporting forms are so rare and fol- 

 iage so mixed on the same shrub that they can hardly be called even 

 a variety in this region. 



Acer grandidentatum, Nutt. Described from a specimen collec- 

 ed by Nuttall on the "Bear River of Timpanagos" in southwestern 

 Wyoming or southeastern Idaho not "N. Montana," as in the Syn. 

 Fl. i : 440; Sargent, Sylva, 2 : 100; Rydberg, Flora, 270 and elsewhere, 

 for Nuttall never was in the present limits of the state of Montana. 

 See remarks under Trifolum andinum, Nutt. (p. 81). "Headwaters 

 of the Columbia River" locality arose from the reference of a speci- 

 men of A. barbatum, Dougl. collected in "Valleys near springs on the 

 west side of the Rocky Mountains, near the sources of the Columbia" 

 (Torr. & Gray, Fl. N. Am. i : 248) from Hooker (Fl. Bor. Am. I : 

 113), a specimen which Hooker afterwards renamed correctly A. 

 Douglasii (Lond. Jour. Bot. 6: 77), so all references of the species to 

 Montana are in error. A. grandidentatum ranges northward to Evan- 

 ston, Wyo. (Nelson) and Pocatello, Idaho (Henderson). 



Ampelopsis quinquefolia, Michx. Often in ornamental cultiva- 

 tion, apparently indigenous along the Missouri and lower Yellow- 

 stone. Poplar, July 12, 1900; Arden, July 15, 1900; Glendive, 1903. 



Vitis vulpina, L. Not infrequent in the bottoms of the Little 

 Big Horn River and reported thence down the Big Horn and Yel- 

 lowstone Rivers. 



Crow Agency, July 15, 1901. 



LOASACE^ 



Mentzelia nuda, Torr. & Gray. Probably not rare in the sandy 

 eastern plains. Miles City, Aug. 16, 1903. 



LYTHRACE^E. 



Ammannia alcalina, n. sp. 



A low annual, 8-12 cm. high, glabrous, divaricately branching from 

 the base : leaves oblanceolate, narrowed abruptly to an acute or ob- 

 tuse apex, sessile and somewhat auriculate at base, often purplish, 



