400 BOTANICAL GAZETTE [May 
from cherry gum, and the crystalline precipitate stained red with phloxin. It is 
not difficult to see that his evidence is hardly conclusive, since the material con- 
densed is not known, and the product of the condensation is evidenced by the 
uncertainty of a stain. If, as seems probable, enzymes capable of condensing the 
simplex carbohydrates into more complex ones exist in plants, their demonstration 
and study is very important to plant need There is need, however, of far 
more conclusive methods.—Wm. Cro 
River dunes.—A study of the Si of the river dunes of Illinois by 
GLEASONS? proves them to be very similar to those of Lake Michigan, although 
differing somewhat in the sand-binding plants that assist in their formation 
These are notably Ceanothus ovatus, Panicum virgatum, and Rhus cndoliee 
The first forest stage is characterized by the dominance of Quercus velutina, with 
which is associated Q. marilandica in the Oquawka area. The underbrush in 
this forest consists almost entirely of young trees of the same species. The suc- 
cessional stages to the maple forest are suggested, and a more exhaustive treatment 
of the relation of the different associations promised for the near future.—Geo. D. 
FULLER. . 5 
Leaf position.— BASSLER investigated the effect of decapitation upon the posi- 
tion of adjacent leaves. He reportss+ that the youngest leaves react by erecting 
themselves more, unless a branch has already developed in the axil, in which case 
the branch erects itself. The closer the leaf to the cut, the more the erection, but 
wounding without decapitation has no effect. Light does not influence the reac- 
tion; gravity slows it. BAssLER was unable to determine or analyze further 
the cause of the reaction.—C. R. B 
Parthenocarpy.—Lonco, in testing the effects of preventing pollination in 
diclinous flowers, found that a dozen flowers of Diospyros virginiana L., unpoll 
nated, set fruit as well as the pollinated ones.ss_ The fruits matured, but the ooh 
were merely coriaceous brown laminae, within whose seed coats was only the exces- 
sively developed tapetum of the embryo sac. Diospyros Kaki L. was already 
known to be parthenocarpic.—C. R. B. 
State Acad. Sci. 2:19-26. 1909. 
54 BASSLER, FRIEDRICH, Ueber den Einfluss des ga tg auf die Richtung 
der Blatter an orthotropen Sprossen. Bot. Zeit. 6'71:67-91. 1909. 
55 Loncg, B., La ee nel enicetas virginiana L.. Rendic. R. Accad. 
Lincei, Cl. Sci. V. 18:632-635. fig. 
53 GLEASON, Henry A., The vegetational history of a river dune. Trans. Ill. 
19 
