260 
characters from them, as of certain cespitose rhizomes especially, 
it is almost impossible to determine the age. The study of the 
stem does not show any result applicable to classification, and 
though as regards the leaf there are structural differences, the 
author concludes that the anatomical study of the genus is not an 
appreciable help towards the determination of the species. 
A. M. V. 
Remarques sur Quelques Espéeces du Genre Polygonum de l’ Her- 
bier du Fardin Botanique de |’ Etat a Bruxelles, par Robert 
Keller. (Compt. Rend. Séan. Soc. Roy. Bot. Belg. Année 
1891, 44-49). 
The references to American species of this genus make the 
article one of special interest to our botanists. The author has 
been able to note numerous varieties and modifications in the 
following species: Polygonum sagittatum, P. Metsnerianum, P. 
pedunculare and P. polymorphum. The first named is divided 
into Meisner’s two principal varieties, Szbiricum and Americanum, 
but the claim is made that this does not sufficiently differentiate, 
especially between specimens of the latter group, and a new 
variety, pubescens, is described, from specimens collected in “ wet 
grounds near Troy, N. Y., Leg. A. Puissant, 1870.” In the 
last-named species the variety folzosum is described as new. The 
author’s method of still further subdividing varieties appears to 
be decidedly of the hair-splitting order, and we hardly feel like 
adopting such a system as includes Polygonum polymorphum, 
Ledeb., var. foltosum, modificatio g/aucescens and mod. latifolia, 
Keller. A. M. 
Editor’s Notices, 
On account of press of other material, the “Index to Recent 
Literature Relating to American Botany ” is omitted this month. 
It has come to our knowledge that copies of a reprint were 
mailed to some subscribers instead of the July number of the 
BULLETIN. All who failed to receive this number may obtain 
it by notifying the editors. It is also requested that any copies 
of the reprint in question be returned. 
