a2 AMERICAN MIDLAND NATURALIST 
date is not the beginning of scientifie botany or nomenclature 
will reject Negundo as a homonym, as it was first applied to the 
plant called Vitex Negundo, and can not be applied to any other. 
The Box-elders are exclusively North American in their 
range or origin, and until quite recently three or four species had 
been recognized. Rulac Negundo (Linn) A. S$. Hitchcock, the 
type of the genus, Rulac mexicana (DC). from Mexico and Guata- 
mala, Rulac californica (A. Gray), from California, and finally 
Rulac texana (Pax) Small, of the South by some botanists. Dr. 
N..L. Britton* in 1908 published two species from the west and 
especially Rocky Mountain Region. The two species were pub- 
lished under Acer, as Acer interior, and Acer Kingi. A number 
of botanists have accepted Nuttall’st species, Negundo fraxini- 
folium as a distinct plant from the eastern Atlantic coast tree. 
His name is however, untenable as Rafinesque published in 1808, 
a Negundium fraxinifolium, a species which like many of that 
author, is not sufficiently distinct from the type to deserve recog- | 
nition, and is undoubtedly some form of the type. Nuttall’s plant 
is beyoud doubt our middle western tree as his description plainly 
indicates. He does not refer to the eastern plant at all, though 
he must have known of it. Dr. Britton evidently included Nut- 
tall’s Negundo fraxinifolium in his Acer interior. The type of the 
latter is from the far west, a pubescent plant hitherto taken for 
Rulac texana (Pax) Small, and mistakenly so. 
Concerning the identity of the plant called by authors Rulac 
texana and especially most plants labelled so in herbaria, much - 
confusion has arisen. ~The real Rulac texana, or Acer Negundo 
var texanum{ Pax, later called by Pax himself Acer californicum 
var fexanum,§ is based on a certain pubescent form of our southern 
states the type or cotype sheet of which is in the United States 
National Herbarium, No. 18099, and is Lindheimer’s No. 360 
from Texas. The first publication of the plant as Acer Negundo 
var texanum Pax, 1885, included several broad leaved plants, 
Dandridge’s from Tennessee and Rugel’s from Florida, also in 
the U.S. National Herbarium which are only forms whose terminal 
leaflet is wider than long. All these have been examined by me 
Britton, N. L. North American Trees, 1908, pp. 655, 656. 
Nuttall, I> Genera of N. Amer. Plants, p. 253. 1818. 
Pax in Engler’s Botanisches Jahrbuch III., (1885), p. 327. 
Pax in Engler’s Bot. Jahrb. XI., (1889), p. 75. 
ett + 
