Nov., 1906.] 
Pubescence of Ohio Plants. 
1 7 
Phlox pilosa; for appressed pubescent leaves Hydrophvllum vir 
ginicum; for ciliate leaves Valeriana sylvatica. 
Only 37 of the 904 pubescent plants are stellate-pubescent, 
but these are very striking. The butternut, Juglans cinerea, has 
stellate pubescent leaves, and also four of the oaks; Quercus nana, 
Quereus marylandica, Quercus minor and Quercus prinoides. 
The most pronounced of this type, however, are the two crotons, 
Croton capitatus and Croton monanthogvnus. 
Of the glandular pubescent forms there are 58. Many plants 
have stems of this type without having the leaves to correspond. 
About half of the roses, as well as Rhexia virginica and Scutel¬ 
laria cordifolia have glandular hairs on the stems. One of the 
most striking forms in the plant kingdom, the Drosera or sun¬ 
dew, belongs to this group. 
There are 67 tomentose forms but all of them are not constant 
throughout their whole life. About one-half of those which are 
tomentose when young become either glabrous, glabrate or 
slighltv pubescent when mature. Many of the oaks, among 
them Quercus platanoides, and Quercus minor, are densely to¬ 
mentose on the under side of the leaves. The young twigs of 
Quercus minor are also tomentose. Viburnum alnifolium is in¬ 
teresting in being one of the few which is _stellate-tomentose. 
532 plants were found to be entirely glabrous, that is, having 
both sides of the leaves and the twigs entirely free from hairs 
throughout their whole life; but 1019 were found to have one 
or more glabrous parts. The spring beauty, Claytonia virginica, 
and wake-robin, Trillium grandiflorum, are common examples 
of the former; Cercis canadensis and Aster laevis of the latter. 
Of the glaucous forms there are 59. The glaucous bloom of 
twigs and leaves is identical with that on some fruit, such as 
plums and grapes, but that on leaves is not usually so noticeable. 
It may be seen on the under side of the leaves of Salix glaucophyl- 
la and Salix myrtilloides, and on the stems of Vitis bicolor and 
Helianthus grosseserratus. 
The granular and scurfy forms are comparatively few in num¬ 
ber, only about 24 of the former, and 34 of the latter. The upper 
surfaces of the leaves of Silene armeria and of Amaranthus bli- 
toides are granular. All of the chenopods are scurfy. 
This leaves only those which are resin-dotted, punctate, or 
have peltate scales. There are 106 in the division, and it is per¬ 
haps the most interesting group of all. Beautiful peltate scales 
are found on Hicoria minima and on Chamaedaphne calyeulata. 
Resin-dots are found on many, among them being Ribes 
floridum, Gaylussacia resinosa and Glecoma hedercacea. The 
most strikingly punctate are the polygonums and the hypericums. 
