426 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
H. H. Bartlett ( Amer . Journ. Bot., 1922, 9, 79-92). The tropical 
Pestalozzias have not been well defined. P. Guepini is the general 
name given to those that grow on Hevea , and the authors of the paper 
have paid special attention to that one. They have secured by culture 
thirty-five different strains which can be allocated to fourteen groups, 
each group containing one or more strains that cannot be placed in any 
other group. A. L. S. 
Studies in the Genus Gymnosporangium. IV. — B. 0. Bodge 
(Amer. Journ. Bot., 1922, 9, 354-65, 1 ph, 7 figs.). The writer has 
investigated the distribution of the mycelium and the subcuticular origin 
of the telium in Gymnosporangium clavipes. He describes the host 
leaf and the area of infection by the parasite — directly on the leaves or 
in stems at the edges of the decurrent leaf -bases. In later years, as 
cork is formed, sori arise and break through in the ordinary manner. 
The teleutospores grow out from the subterminal cells of the basal 
primordium, the terminal cells having become disorganized, and being 
swollen function as buffer cells. The mycelium is first found in the 
cuticularized layer of the epidermal cells, later in the mesophyll. 
A. L. S. 
New Biological Species of the Type of Puccinia sessilis. — 
Eug. Mayor {Bull. Soc. Mycol. France, 1922, 38, 34-41). The author 
noted from year to year in the Jura an abundant growth of aecidia on 
Paris quadrifolia, Convallaria majalis , Polygonatum multiflorum, and 
P. verticillMum. The Puccinia of these hosts formed teleutospores and 
uredospores on Phalaris arundinacea, but as no plant of that type grew 
in the area Mayor looked round for another alternate host, and decided 
that Festuca silvatica must be the one. His surmise was correct, and 
he proved it by infection experiments. There are thus two secidia on 
Paris quadrifolia, etc., agreeing exactly in their morphology, but differ- 
ing absolutely in their alternate hosts, the one being Phalaris arundi- 
nacea, the other Festuca silvatica. A. L. S. 
Vegetative Vigour of the Host as a Factor influencing Suscep- 
tibility and Resistance to certain Rust Diseases of the Higher 
Plants. — M. A. Raines {Amer. Journ. Bot., 1922, 9, 183-203, 215-38, 
2 pis.). As a result of prolonged and varied culture experiments, the 
author considers that evidence is forthcoming of a direct relation be- 
tween the vigor of the host and the virulence of the disease. The 
results are directly affected by the age and maturity of the host. 
Results also vary according to species. In some of the experiments 
there was an increased incidence of infection with depression in the 
growth rate of the host. A. L. S. 
Contribution to the Knowledge of UstilagineaB. II. — F. Rawit- 
SCHER {Zeitschr. fiLr Botanik, 1922, 14, 273-95, 2 pis.). The writer 
has worked at the cytology of a number of fungi belonging to this 
family. In Tilletia Tritici reduction division of the nuclei takes place 
in the spore, and there are as many nuclei formed as later there are 
sporidia on the promycelium. In Gintractia Montagnei the first nuclear 
division takes place in the germination of the promycelium. There are 
