39^ TKANS. ST. LOUIS ACAD. SCIENCE. 



hair on the young leaves, while in flowering Texan specimens it seems to 

 be entirely wanting. 



j£. Wtsli'zeni, A. DC. With his usual acumen, A. DeCandolle discov- 

 ered this species in a small fruiting specimen, brought by Dr. Wislizenus 

 in 1851 from the American Fork of the Sacramento River, but, through 

 a mistake of mine, he located it near Chihuahua. Since then nothing fur- 

 ther, I believe, has been published about this remarkable oak, though an 

 abundance of material and very full notes have been gathered by different 

 collectors, principally by Prof. W. H. Brewer and Dr. H. Bolander. 



This species is found throughout the western parts of California from 

 Shasta to San Diego, principally in the region of the foot-hills, but does 

 not ascend the higher mountains. In some localities it makes a "magnifi- 

 cent tree" 40 to 60 feet high, with a trunk occasionally 6 feet in diameter, 

 but branching 5 or 6 feet from the ground, as most of the large Californian 

 oaks of both groups are wont to do. On the coast ranges from Monte Dia- 

 blo to San Diego it also occurs as a small shrub with small leaves. 



The bark is pale and smoothish in younger, very rough and black in 

 older trees. The firm, leathery leaves persist 14 or 15 months on the 

 branches ; they vary excessively, often on the same tree, from broad ovate 

 to narrowly lanceolate ; cordate, obtuse, or acute at base ; the margin 

 entire, or with a few teeth or sharply and closely dentate ; shoots or young 

 trees have usually dentate, old and fertile ones more commonly entire 

 leaves. In the earliest age the leaves are very slightly concave, and in 

 vernation imbricate; they bear on both sides articulated hair, but soon 

 become glabrous ; the full grown leaves are mostly dark green and shin- 

 ing, and delicately reticulate, principally on the upper surface. They are 

 usually 2-4 inches long and half as wide, or rarely narrower; petioles 

 5-9 lines long; in van frutescens the leaves are only \-\h inches long, 

 oval, entire, or often very sharply and deeply lobed-dentate ; petioles 1-2 

 lines long. 



The rhachis of the aments is stellate-canescent, or nearly glabrous ; 

 calyx lobes 5 or 6, large and broad, nearly glabrous or ciliate-bearded; 

 anthers 3-6, often pointed. Bractsof the sessile (or often peduncled) female 

 flowers large, orbicular, membranaceous ; the long, recurved styles not 

 rarely 4 or 5 in number. Acorns always elongated, 9-18 lines long, im- 

 mersed ^ to f in the cup, which I find varying from 6-11 lines in depth 

 and 5-6 lines in width; cup scales elongated, acutish, light brown, and 

 nearly glabrous. 



On one hand this species approaches to ^. agri/oli'a, with which it has 

 often been confounded, and on the other to .1^. Sofioinensis. 



Dr. Kellogg, in Proc. Cal. Ac. 2, 36 (DC. Prod. 16, 2, 79), scantily de- 

 scribes an oak under the name of. ^. More/ius, which may belong here. 



J^. myrtifolia, Willd. Willdenow's description of the foliage, which 

 cannot possibly refer to any other oak, together with his locality, makes 

 it certain that in Dr. Mellichamp"s very complete specimens we have 

 his plant before us, and, thanks to him, I can now reestablish this 



