1919] SARGENT. NOTES ON NORTH AMERICAN TREES. V 63 



are ovate, longer than broad, abruptly acuminate at apex, subcordate or 

 rarely truncate at base, finely crenately serrate, 12-15 cm. long and 10-12 

 cm. wide. The flowers and fruit do not differ from those of the common 

 Cottonwood, and the angular branclilets, which have often been considered 

 a specific character of this tree, have no significance for such bninchlets occur 



^f' 



^f' 



at Shelburne Point, Chittenden County, Vermont; near Rochester, Munroe 

 County, New York; from an island in the Delaware River above Easton, 

 Northampton County, Pennyslvania; North Bend on the Ohio River, 

 Hamilton County, Ohio; banks of the Potomac River opposite Plummer's 

 Island, about Bare Hills and near Copper Mine, Baltimore County, Mary- 

 land; banks of the Chattahoochee River at Columbus, JVIuscogee County, 

 Georgia; River Junction, Gadsden County, Florida; Starkville, Oktibbeha 

 County, and Artisia, Lowndes County, Mississippi. 



The Popidiis angulata of the younger Michaux, although he did not de- 

 scribe or figure the staminate flowers, is probably the P. balsamifera of Lin- 

 naeus, but it is impossible to determine if the P. angidata of Aiton is the P. 

 halmmijcra of Linnaeus or the tree now cultivated in Europe as P. angnlata, 

 on which the scales of the flowers are dentate, not fimbriate at apex. Trees 

 with such scales have not been found growing wild in the United States, and 

 it is possible that all the trees with these peculiar scales have been propa- 

 gated from one abnormal individual. For the common Cottonwood of the 



eastern 



if. 



smaller ovate-delloid leaves, the following name can be adopted: 



virginiana 



/? 



part, 

 — P, 



deltoidea var. angulcda Sargent, Trees and Shrubs, ii. 212 (1913), in part. 



The leaves of northern trees of this variety are quite glabrous, but south 

 of the Potomac and Ohio Rivers many individuals occur on which the under 

 side of the midribs and pruicipal veins iire pilose, especially early in the 

 seiison. This form, which is probably the P. angidata var. missouricnsis 

 A. Henry in part and the P. deltoidea var. angidata Sargent in part, may 

 be called 



Populus balsamifera var. pilosa, n. nom. 



Betula papyrifera var. elobata, n. comb. — B. alba var. elohata Fernald 

 in Rhodora, xv. 169 (1913). 



var. occidentalis, n. comb. — B, occidenialis Hooker, 



papyrifera 



Fl. Bor. Am. ii. 155 (1839). — P. papgracea var. occidenialh Dippel, Laubh. 

 II. 177 (1892). — P, Lyalliana Koehne In Mitt. Deutsch. Dendr. Ges. viii. 

 53 (1899), nom. nud. — B, papyrifera y^v, Lyalliana Koehne apud Schelle 

 in Beissner, Schelle & Zabel, Handb. Laubholz.-Ben. 55 (1903). 



Betula papyrifera var. subcordata, n. var. — P. suhcordata Rydberg apud 

 Butler in Bull, Torrey Bot. Club, xxxvi, 496, f. 15 (1909). 



