BOX ELDERS 149 



sent me his paper on Box-elders, real and so-called/ After having 

 read and compared these two papers, I began a systematic examina- 

 tion of the Box-elders growing about Courtney, Missouri. Some 

 five or six years ago I decided that we had wo, or possibly three, 

 species of Negundo here, and was taking the common tree of the 

 river bottom here for A^. Negundo, and was referring the other 

 with some doubt to N. Texanum, a species I was wholly un- 

 acquainted with. A large Box-elder is growing in my back yard, 

 which I have known for more than 25 years, and this tree I thought 

 might be the real A^. Negundo. In rocky woods on the hills 

 around, there is another tree that has densely-velvety twigs, which 

 years ago I referred to A^. Texanum. Fresh flowering specimens 

 of these two trees were sent to Dr. Rydberg last April, who identified 

 them as A^. Negundo and A^. interius, respectively, the latter a 

 tree supposed to inhabit the Rocky Mountain region of Western 

 Nebraska and Western Kansas. As the season advanced and the 

 fruit began to mature, I decided after a careful study of several 

 hundred trees in Jackson County, that these two trees were more 

 properly referred to N. NuUalii and A^. interius. 



I have lately sent good fruiting specimens of these two trees 

 to Dr. Nieuwland, who writes me that they are good specimens 

 of A''. Negundo and N. Nuttallii. As there seems to be some ob- 

 scurity about these species, I shall give a short examination of the 

 principal characters accorded each, and compare these with those 

 of the trees I now refer to them., that we may the more fully 

 understand them. 



Dr. Rydberg in his key to the species of Negundo^, separates 

 the species into two groups, the first with branches of the season 

 glabrous, or with a few scattered appressed hairs, the second with 

 branches densely-velutinous with short spreading hairs. In the 

 first section he places N. Negundo and A^. Nuttallii, and in the last 

 section A^. interius and A^. Texanum. 



Dr. Nieuwland agrees with Dr. Rydberg in this distinction 

 so far as A". Negundo, N. Nuttallii and A^. interius are concerned, 

 but he does not recognize A^. Texanum as of specific rank, putting 

 it with A^. Calif or nicum.^ Of the four species mentioned above 

 as given by Rydberg in his key, he distinguishes them by the 

 character of the fruit, which in N. Negundo and A^. Texanum is 



1 Midland Naturalist, 2:6, p. 129-140. Nov. (191 1.) 



2 Rydberg, 1. c. p. 54 3 Nieuwland, 1. c. p. 139. 



