156 BOTANICAL GAZETTE [FEBRUARY 
colored plates are used to show the author’s interpretation of the transformation 
of the resting mycoplasm into the mycelium condition of the rust.—J. C. ARTHUR 
Light relations at high altitudes—Wirsner’s study of the Lichtgenuss of 
plants, already comprehensive for varying latitudes, has now been extended?! 
to include high altitudes. During a period of thirty days from Aug. 16, photo- 
metric observations were made in the Yellowstone territory at eight altitudes 
ranging from 515 to 2210™ above sea level. The investigation shows that the 
behavior of plants with advancing latitude does not agree with that manifested 
under increasing altitude. The relative amount of available light appropriated 
by arctic plants increases inversely with the distance from the pole. This relation 
holds with increasing altitude only to a certain limit, above which a smaller and 
smaller share of available light is appropriated. The cypress habit of growth 
is evidently intended to protect from increased intensity of light, whether this 
accompanies low latitudes or high altitudes. This seems all the more probable 
heat, which is manifested by other species that do not show it at lower levels.— 
Raymonp H. Ponp. 
Tomato rot.—Von Oven”? has recently described a disease of tomatoes caused 
by Fusarium rubescens Appel & Von Oven. This fungus causes a rotting of 
the tomato fruit, and evidently does not belong to the fungi in this group producing 
stem rot or wilt disease, although in cultures the pink and violet shades char- 
acteristic of the latter are also produced by this new species. As it is impossible 
to separate the species of Fusarium on morphological grounds, von OVEN has 
attempted to distinguish this species at least from several disease-producing 
fusariums by their physiological characteristics. It is thus distinguished from 
F. Solani, F. putrefaciens, and F. rhizogenum. In cultures on sterilized potato 
small sclerotia were formed, which produced conidia after being exposed during 
December and January. The author concludes that this is a hibernating stage 
of the fungus, although he does not mention finding them in nature—H. HassEL- 
BRING. 
Axillary scales of aquatic monocots.—As aquatic monocotyledons are by 
some held to be modern representatives of the more primitive angiosperms; 4S 
these forms may have been genetically related to some such type as Isoetes; and 
as he regards the ligule as an important phylogenetic organ, Grsson?3 has made 
a study of the vestigial structures of the following families: Potamogetonaceae, 
21 WIESNER, J., Untersuchungen iiber den Lichtgenuss der Pflanzen im Yellow- 
— und in anderen Gegenden Nordamerikas. Sitzungsber. Kaiserl. Akad. 
Wiss. 
. Wien, Math.-Naturw. 2 lee II4':(pp. 74.) figs. 2. ; : 
22 ne E. von, Ueber eine Fusariumerkrankung der Tomaten. Landw. 
Jahrb. 34:489-520. pls. 5, 6. fig. I. 1905. 
23 Gipson, R. J. Harvey, The axillary scales of aquatic monocotyledons. Jour. 
Linn. Soc. Bot. 3'7:228-237. pis. 5, 6. 1905. 
