150 McATEE: VIBURNUM AND THE CAPRIFOLIACEAE 
margins in these species may be of iriterest. In both, the leaf 
margin is more or less inrolled and the revolute character is most 
marked in V. nudum, which is described as having chiefly entire 
leaves. Viburnum cassinoides is described as generally crenulate- 
denticulate; however, the manuals note that each species occa- 
sionally has the leaf form of the other. If the revolute margin of 
the leaf of V. nudum be unrolled, crenulations are visible; thus, 
while the leaf really possesses the character supposed to be distinc- 
tive of V. cassinoides, the rolling in of the margin hides it and gives 
the leaf the appearance of entirety. The crenulations also are 
visible in many V. nudum leaves without unrolling them, that is, 
the margin is only folded back and the crenulations lie flat against 
the lower surface of the leaf. Both types can be found on a 
single plant as can also both long and short peduncles. The most 
reliable character for separating V. nudum and V. cassinoides is 
the shape of the pit of the fruit. The former has a simple, thin, 
lenticular pit, the latter an elongate, fusiform and sulcate one. 
Even these differences are more or less obscured by variations in 
certain specimens, but extreme southeastern V. nudum seems typi- 
cal and so do northern specimens of V. cassinoides. Despite 
general inosculation of characters, therefore, the writer is inclined 
to rank these two forms as species, which hybridize more or less 
throughout the extensive common portion of their ranges. 
Whorled leaves in Caprifoliaceae.—The possession of whorled 
leaves has a number of times been cited as one of a combination of 
characters distinguishing the Rubiaceae from the Caprifoliaceae. 
Seeing that this does not hold, the writer has noted, and in most 
cases collected, specimens showing verticillate leaves in various 
Caprifoliaceae. Such leaves are found most frequently on strong 
root-shoots, and according to the theory elaborated by Dr. R. T. 
Jackson,* indicate the ancestral condition. Species of Viburnum 
on which whorled leaves have been seen include: V. Opulus, V. 
acerifolium (whorled branches also), V. dentatum, V. pubescens, 
V. Lentago, and V. Lantana. Sambucus canadensis with verticillate 
leaves has been collected also, as well as the following species of 
Lonicera: L. japonica, L. tatarica, L. fragrantissima, L. hispidula, 
and L. thibetica. The last species as seen in the Arnold Arbore- 
: * Mem. Boston Soc. Nat. Hist. 5: 89-153. pl. 16-25. April, 1899. 
