134 AMERICAN MIDLAND NATURALIST 
the midland, so that various graduations are found from that of 
his type to that of the plant of the Atlantic States. As Dr. 
Britton states, however, of the western type “the features 
which while individually insignificant are collectively sufficient 
to warrant its recognition as a species,’’ one may also say the 
same of the Midland Box-elder first described by Nuttall. The 
leaves are thick and firm and very veiny, drying greenish whereas 
those of R. Negundo dry brownish and are extremely thin and 
membraneous, the first bodies are perfectly glabrous in Nuttall’s 
plant, minutely pubescent in the eastern type. The middle western 
plant has larger fruits usually in shape like those of R. interior; 
the leaves differ in being composed commonly of more 
than three leaflets even in fruiting branches. The sterile and 
growing shoots have usually 5 to 7 leaflets and very often 7 
to 11. Leaves with eleven leaflets are bipinnate a character 
that did not escape Nuttall nearly a hundred years ago. The 
lower leaflets at the base and the terminal have again become 
compounded into pinnately trifoliolate members. Such leaves 
of 9 to 10 or 11 leaflets may be found on nearly any tree in our 
locality. The most obvious character of the midland plant is that 
of the pale bluish glaucous twigs, The bloom often persisting 
several seasons on old stems. As the plant was recognized by 
Nuttall, but under a name previously taken, I propose in his honor 
to call the plant, Rulac Nuttallii. 
Bourgeau in 1859 published in a list the name Negundo Fraxinus 
for a plant from Saskatchewan. A plant or cotype of this is in the 
U. S. National herbarium, No. 292221. It is not very satisfactorily 
labelled, and the publication is not accompanied by any diagnosis; 
hence is a nomen nudum. The specimen supposed to be that of 
Bourgeau mentioned above is, however, undoubtedly the same 
plant as R. interior of Britton. 
Some of these questions of synonymy and explanation for 
rejection of names referred to, might perhaps have been desired 
when Dr. Britton published Acer interior. As his work is, however, 
more or less popular in treatment, we can readily see why dis- 
cussions of homonyms and synonyms and nomina nuda with other 
complicated matters of nomenclature, had better been entirely 
omitted by him. There are those, however, who are not quite 
able to see why Nuttall’s name should have been omitted for either 
* Bourgeau, Jour Linn. Soc. IV., (1859), 9. 
