FLOWERING PLANTS OF NANTUCKET 377 
to accept it as essentially distinct from Q. prinoides; nor have I 
yet encountered any trees so nearly intermediate between the two 
as to have the appearance of being hybrids. 
It may be noted that the anthers of Q. rufescens are perceptibly 
smaller on relatively shorter filaments than those of Q. prinoides, 
that is to say this proved to be true in numerous cases when I 
was enabled to make satisfactory comparison in the field. 
QUERCUS ALBA X RUFESCENS? An oak about five feet high of 
somewhat straggling form, observed near the Wigwam Ponds, 
July 6, 1912, conveyed a strong impression of being a hybrid 
between Q. alba and Q. rufescens. The pubescence of the leaves 
and branchlets is much as in Q. rufescens, while the size of the 
leaves, some of them 14 X 8 cm., and their deep lobing seem to 
point rather clearly to Q. alba as one of its parents. 
QUERCUS ILICIFOLIA X VELUTINA Rehder. A thriving oak, a 
hybrid, there seems little reason to doubt, grows in the dense 
- thicket on the western side of Dyleave Swamp. It was about 
twelve feet in height and nineteen inches in girth low on the trunk 
June 26, 1910. In its foliage it is very distinct from any other 
Nantucket oak that I have seen, and the forms of its leaves and 
their pubescence suggest, rather convincingly, I think, a mixed 
origin from the two oaks above indicated as probable parents. 
Such a hybrid was described and figured by Mr. Rehder (Rhodora 
3: 137: pl. 24. 1901). The leaves of the Nantucket tree show 
remarkable variation in form, and have no close similarity to 
those figured by Mr. Rehder, but the pattern characters by which 
they differ appear to be such as might well result from a crossing 
of Q. velutina with the form of Q. ilicifolia having narrow deeply 
cut leaf lobes rather than with the more usual short-lobed form. 
They are, however, considerably larger than those which Mr. 
Rehder has described, the largest being 17 X 14cm. When young 
the lower surface is whitened with a close tomentulose pubescence, 
although in less degree than those of Q. ticifolia, but this is im- 
permanent, the leaves becoming quite green beneath in age. The 
cups of some old acorns found beneath the tree were turbinate, 
their scales tomentulose to partly glabrate; nuts conic ovoid or 
oblong, 10-14 mm. long, tomentulose and strigose towards the 
apex. 
