452 BOTANICAL GAZETTE [MAY 
dry sandy soil sometimes reach a height of 20 m. and form trunks 40-50 cm. in 
diameter, covered below with nearly black deeply furrowed bark. In the 
neighborhood of Orlando this tree is called silver oak from the pale color of the 
smooth upper stem and large branches. On the Florida trees sometimes occur 
lanceolate or oblong-elliptic entire leaves which I have not seen on the speci- 
mens collected near Bluffton by MELLIcHAMP. In Florida the leaves of these 
trees begin to fall in December and fall gradually during the winter. My 
attention was first called to the silver oak in April r915 by C. H. BAKER of 
Zellwood, near Orlando. It has been since: collected in Orange County and in 
the neighborhood of San Mateo by T. G. Harbison and myself. 
QvuERCUS DUBIA Ashe, Jour. Elisha Mitchell Sci. Soc. 11:93. 
1894.—Q. atlantica Ashe, Proc. Soc. Am. Foresters 11:88. 1916; 
Q. sublaurifolia Trelease, Proc. Am. Phil. Soc. 56:52 (nomen 
nudum). 1917; (Q. cinerea Xlaurifolia).—The specimens which I 
_believe represent this hybrid all have rather thick leaves pubescent 
on the lower surface and pubescent branchlets. The leaves vary 
greatly in shape and size; those of the type of Q. dubia from 
Abbotsford, Bladen County, North Carolina, are oblong, acute 
at apex, unsymmetrical and rounded at base, sometimes slightly 
falcate, 14-16 cm. long and 5.5-7.5 cm. wide. Specimens with 
similar leaves were collected at Jacksonville, Florida, by A. H. 
CURTISS many years ago. Unfortunately these specimens are not 
numbered or dated. He considered them a large-leaved form of 
Q. laurifolia. The type of Q. atlantica collected by Ashe at Lumber 
City in southern Georgia has many of the leaves obovate and 
rounded at apex and others elliptic or lanceolate and acute, resem- 
bling in size and shape those of Q. laurifolia and sometimes, like 
those of that species, they are slightly lobed toward the apex. The 
fruit of this hybrid is nearly sessile or distinctly pedunculate. On 
some trees it has the shallow cups of Q. laurifolia and on others cups 
as deep and broad as those of the large fruited forms of Q. cinerea. 
The trees of this oak which I have seen in Florida were not more 
than 12 m. high, with trunks 35-40 cm. in diameter, covered with 
dark deeply furrowed bark resembling that of Q. cinerea and with 
stiff erect branches forming an open head. 
In addition to the specimens collected by Curtiss and AsHE I have seen 
specimens which seemed to belong to this hybrid collected by T. G. HARBISON 
in 1917 at Abbottsburg, Bladen County, North Carolina; Saint Helena Island 
