QUERCUS MACDONA.LDI. 25 



same inability to divest itself of its dead foliage in autnmn. This I observed first in the 

 mountains of Colorado, and afterwards in those of New Mexico ; and the fact seems suffi- 

 cient to decide the whole question of the real affinities of this tree. No one seeing this 

 and Q. undulata growing together at winter time, can possibly accede to the proposition 

 that they are one species. 



Another kind of proof that the Rocky Mountain white oak is a close ally of the east- 

 ern forest tree, lies in the qualities of the wood. Before the day of railroads in Colorado, 

 while ox-teaming was the only means of freight-transportation, the Quercus Gambelii was 

 well known to teamsters as the only tree of the whole Rocky Mountain region out of whose 

 young saplings an ox-bow could be made. The straggling evergreen, Q. undulata^ would 

 doubtless have failed to exhibit the necessary degree of flexibility, even if stems of suffi- 

 cient length could have been found. 



To this defense of the reinstatement of Nuttall's species, I am glad to be able to add 

 the remark, that Mr. Hemsley, in his great work upon Mexican botany, has reached the 

 same conclusion after a study of herbarium specimens alone. 



The figure in the report of the Sitgreaves expedition is admirably correct ; taken from 

 an old tree, evidently. This of Dr. Kellogg represents the smoother and more slender 

 branchlet of a young tree. His specimen purports to have come from Mt. Graham in 

 Arizona, whence it was brought by Mr. J. G. Lemmon, whose opinion that it is distinct 

 from Q. undulata, Dr. Kellogg records in pencil. 



I may here introduce a Californian oak which Dr. Kellogg knew not of; one which 

 has indeed, remained thus far unrecognized by botanists. I gladly dedicate it to the 

 worthy donor of this treatise, under the name 



QUERCUS MacDONALDI. 



Description. A small deciduous tree, from fifteen to thirty-five feet high, the trunk 

 rarely a foot or more in diameter, clothed with a thin, close, gray bark, which is rather 

 finely rimose ; branches and twigs slender, numerous, forming a gracefully rounded and 

 rather compact head : branchlets and lower face of leaves rather densely stellate-puberulent; 

 surface of the leaves glabrate in age : leaves about two and a half inches long, on petioles 

 of two or three lines, spatulate-oblong, the upper and broader portion somewhat pinnately 

 lobed, the lobes acutish and mucronulate, the lower and narrow portion entire, inequi- 

 lateral but obtuse at base ; winter buds a line and a half long, ovate, acute, their scales 

 indistinctly ciliolate : fructification annual : acorns sessile ; cup rather deep-hemispherical, 

 strongly tuberculate ; nut ovate-oblong, acutish, less than an inch long. 



