Miss Wheldale, in England, has recently published two papers 
that are very interesting in the same connection. One is “Тһе 
Chemical Differentiation of Species," Biochemical Journal 5: 445 
(1911); and the other is “Тһе Colours and Pigments of Flowers 
with Special Reference to Genetics," Proceedings of the Royal 
Society, Series B, 81: 44 (1909).—E. D. C. 
Under the authorship of M. F. Barrett of the State Normal 
School at Upper Montclair, New Jersey, there has appeared a 
"LEAF KEY TO THE GENERA OF THE COMMON WILD AND 
CULTIVATED DECIDUOUS TREES OF NEW JERSEY.” The author 
apparently realized the impossibility of determining the different 
genera of trees by leaf characters alone, and frequent use is made 
of other but equally obvious characters. Used under the guidance 
of a teacher knowing the trees, the key should prove a useful 
pamphlet to the beginner. Some of the distinctions drawn be- 
tween genera, the hickories and walnuts for example, require more 
botanical judgment than the unaided beginner is apt to have, but 
the key will be a great help in class work, where the instructor 
exercises considerable interpretative helpfulness. Copies may 
be procured from the above address and cost only ten cents each. 
—N. T. 
The September Mycologia includes an article by Bruce Fink 
on the nature and classification of lichens; it consists chiefly of 
collected statements of various botanists with reference to con- 
sidering lichens as a distinct class. About 83 per cent. of the 115 
botanists consulted believe that the lichens should be maintained 
as a distinct group of plants; the balance would distribute them 
among other fungi to the exclusion of the group Lichenes. Forty 
botanists favored maintaining LICHENES, considering it a natural 
group. Europeans are more favorable to this division than 
Americans. Convenience for study is evidently considered an 
_ additional argument for Сое + the group.—J. В 
We are pleased to mention Publication No. 1 of the Botanical 
Society of Western Pennsylvania, issued Nov. 27, 1911. It has 
