ENGELMANN OAKS OF THE UNITED STATES. 383 



specimens seen by me are sessile, the bright brown scales of the cup only 

 slightly thickened at base. 



8. ^>. reticulata, H. B. K., has been found in Southern Arizona by Dr. 

 Rothrock, in the expedition just mentioned. 



9. Q. virens, Ait. A shrubby form is var. maritima, Chapm., Jg. mari- 

 tima, Willd., from which var. dentata, Chapm., cannot be separated ; both 

 have shorter and often larger acorns on shorter peduncles than the spe- 

 cies ; the former is the larger shrub, rarely as much as 10 feet high, with 

 usually entire lanceolate leaves; the latter often bears fruit when only i-i£ 

 feet high; leaves sometimes dentate or sinuate-dentate, 1-2 inches long; 

 vigorous ground shoots occasionally produce broad oval, entire, or dentate 

 leaves, 3-4 inches long and i£-2g wide. 



10. Jg. chrysolepis. Liebm., has so often been spoken of in the foregoing 

 pages that little need be added. Its fructification was misunderstood until 

 the abundant material, brought together by Prof. W. H. Brewer for the 

 California State Survey, permitted me to clear it up. The size of the plant, 

 of the leaves, and of the fruit, is extremely variable ; and even the yellow 

 pubescence, which has given it its name, is neither persistent, nor is it 

 present in all cases. Young vigorous shoots or young trees have spiny- 

 dentate leaves; older trees, especially on fertile branches, usually entire 

 ones. The acorns are sometimes very large and the shallow cup extremely 

 thick: this is the form Torrey (Pacif. R.R. Rep. v. 365, tab. 9) has de- 

 scribed as 4>. crassipocula ; Dr. Parry sends from San Bernardino still 

 larger cups, if inches in the outer 'diameter. Dr. Kellogg's J^>. fuloescens, 

 in Proc. Calif. Ac. 1, 67 & 71, seems (from specimens seen in Hb. Brewer) 

 to refer to the form with middle-sized acorns and cups of the ordinary 

 shape, without that unusual thickening; his Q. vacciniifolia, ib. 1, 96 

 (106 ed. 2) is a small-leaved mountain form. Of this variety specimens 

 are found entirely destitute of the yellow, scurfy pubescence even in the 

 earliest youth. The anthers of this species, usually 10 in number, are 

 always strongly pointed; the broad stigmas are closely sessile. The late- 

 ral position of the ovules has been mentioned. 



11. J£. agrifolia, Nee, the first western oak that became known (1802), 

 is quoted by the author as inhabiting " Nootka Sound " and California 

 perhaps by mistake, as now it does not seem to be known much north 

 of the Bay of San Francisco, and it extends as far south as the southern 

 boundary of the State, but does not ascend the mountains. It is a fine 

 large almost evergreen tree, but makes miserable timber and even poor 

 firewood. The old leaves partially fall off in winter, so that the heads be- 

 gin to look less dense towards spring; in some trees the last leaves have 

 fallen before the young ones are developed, but generally they do not come 

 off entirely before the young verdure covers the branches. Dr. Bolander 

 remarks that occasionally odd-looking trees are observed which in spring 

 retain all their old leaves without bringing forth flowers or young shoots — 

 a state of things which resembles the condition of «^. ckrysolepis, above 

 alluded to; that species, however, performs the function of maturing its 



