Plate XV, Figures 2 & 3: Plate XVII. 



l^ QUERCUS ENGElvMANNI. 



Bibliography. 



QuERCUS OBLONGIFOLIA, Eiigelm., Bot. Calif, ii. 96, in part, not of Torrey in Sit- 

 greave's Report. 



Description. A tree of middle size, twenty-five to forty feet high, with light-colored 

 and rather smooth bark, a trunk from two to three feet thick, the branches spreading to 

 form a well rounded scarcely depressed head : leaves short-stalked, oblong two or three 

 inches long, entire, or sometimes with a few coarse teeth, obtuse or retuse at apex, rounded 

 or slightly cordate at base, those of young shoots sometimes acutish at both ends and 

 coarsely serrate-toothed throughout, texture coriaceous, almost without reticulation, downy- 

 pubescent when 3'oung, glabrous when old : acorns sessile or peduncled ; cup hemispherical, 

 tuberculate; nut oblong, an inch long, lineate. 



Habitat. Mountains of southern California, from the mesas east of San Diego 

 northward to Kern County ; locally known as the Evergreen White Oak, and Live Oak. 



Remarks. This oak appears to be exclusively Californian and peculiar to the south- 

 em portion of the State. It is quite as distinct from the true Q. oblongifolia (which I have 

 already referred as a form to Q. undulata grisea) ., as the Californian Q. dumosa is from its 

 New Mexican counterpart Q. undjilata. Its best specific character is found in the large 

 striped acorn ; those of the more easterly species with which it has hitherto been confounded 

 being less than half as large and in no degree lineate. The lineation has been well 

 brought out by Dr. Kellogg notwithstanding that he followed Dr. Engelmann in the con- 

 fusing of the two species. The Californian tree is much larger in all its parts, and the 

 leaves are quite commonly retuse or emarginate. 



The suggestion that our tree is specifically different from the original Q. oblongifolia 

 was favorably entertained by Dr. Engelmann, to whose memory I dedicate it. 



