198 
Notices of Books. 
What we have here is practically this : The old genera Vitis, 
A mpelopsis, and Cissus are re-established in modified form, and from 
each off-shoots have been removed as new generic types. Thus 
Ampelocissus and Clematocissus include members lopped from Vitis , — 
the former taking monoeciously polygamous forms which have non- 
calyptroid corollas; the latter, monotypic, having the character of 
Ampelocissus , but with a smooth long style and almost dry fruit, — and 
Tetrasiigma, an old section of Vitis on account of its stigma, is sepa- 
rated as a distinct genus. Ampelopsis is restored in the restricted sense 
instituted by Rafinesque for the forms of which Michaux’s A. cor data 
is the type, whilst those which are the true Virginian Creepers, and 
with which since the work of Torrey and Gray the genus has been 
so widely associated, are now separated from it as Parthenocissus , 
their obsolete disk being a chief differential character. Cissus has given 
off to Rhoicissus its pentamerous forms with marcescent corolla and 
annular disk : and lastly, Landukia is founded upon a single Eastern 
species, which has been variously referred by authors to Vitis, Am- 
pelopsis, and Cissus. The larger of the genera thus created, Vitis, 
Ampelocissus , and Cissus , are divided by M. Planchon into sections. 
In defence and explanation of this view of affinities in the family, 
M. Planchon refers in his Introduction to the relative value of the 
characters in which he has sought diagnostic marks and aids to 
generic grouping, and points out that the leaves in a family which has 
so many heterophyllous forms are naturally of quite secondary 
importance. The same may be said, though with less force, of the 
pentamery and tetramery of the corolla, for Ampelocissus has both 
forms in the same inflorescence. Whilst the calyptroid corolla is a 
general and normal feature in Vitis, it is present also exceptionally 
in Cissus. The constitution of the disk furnishes very important 
characters. Always adnate to the base of the ovary, it is erect with a 
distinct brim in Vitis, Ampelocissus, and Tetrasiigma', a cup with 
nectariferous marginal depressions in Cissus ; an undulate ring per- 
sisting at the base of the fruit in Ampelopsis ; whilst it is reduced to the 
adnate portion without trace of brim in Parthenocissus. The form 
and length of the style are also of importance. It is conical and 
smooth in Vitis, conical and often grooved in Ampelocissus, and it is 
always short in these genera and in Pterisanthes. Cissus has a long 
style. Clematocissus is a transition form with a style almost as long 
as that in Cissus, and Ampelopsis has a style with the stoutness of 
