148 
Pilzkrankheiten der Pflanzen 
BOLLEY, H. S., The complexity of the microorganic population 
of the soil (Science, N. S., 1913, 38 [11 July], 48 — 50). 
This is a critique of the paper by Russell (Science, 37. 519) who 
supports the theory of the great relative activity of Amoebae in partially- 
sterilized soil as accounting for increased productivity. Bolley states 
that he has investigated the toxine theory and the relation of the bac¬ 
terial flora and finds no cereal crop-limiting factors associated with them. 
On the other hand, he places the blame on one or more species of soil 
fungi, including Fusarium , Alternavia, Helminthosporium , Colletotrichum , 
Macrosporium and Ophiobolus. 
Most of these organisms persist in the soil. They may also be 
introduced with seed, manure, etc. By the use of pure uninfected seed¬ 
lings transplanted to infected soil, upon which selected seed was sown at 
the same time, the writer secured 21,8 grams of plump seed per plant as 
against 4,7 grams where the plants germinated and developed in the 
infected soil. Humphrey (Madison, Wise.). 
HEED, H. S. and HOLMES, S. S., A study of the winter resistance 
of the uredospores of P uccini a cor on at a Cda. (Virginia Agr. 
Exp. Stat. Rept. [1911/12] 1913, 78—81; fig. 1). 
By a study of germination of the Crown Rust of Oats it was 
found that under the natural climatic conditions which exist in Virginia, 
this organism can overwinter in the uredospore stage. 
F. A. Wolf (Auburn, Ala.). 
WAWILOFE, N., Über den Weizenbastard Triticum vulgare Vill. Q 
X Tr. monococcum L. cf (Bull. Angew. Botan., St. Petersburg 1913, 
6, Nr. 1, 1—19; 1 Taf.). — [Russisch u. deutsch.] 
Verf. erzielte einen Bastard bei der Kreuzung von Tr. vulgare 
Vill. var. erythsospermum Kcke. ß x Tr. monococcum var. ßavescens 
Kcke. Ç. Er wird genau beschrieben und abgebildet. Über die Beziehungen 
des Bastardes sowie der Eltern zu den parasitischen Pilzen ergibt sich 
folgendes Bild: 
Empfänglichkeit gegen 
bei 
Tr. monococcum 
bei 
Tr. vzilgare 
beim obigen 
Bastard 
1. Puccinia triticina ErIKSS. 
sehr schwach 
stark 
stark 
2. Puccinia graminis PERS. . 
schwach 
stark 
stark 
3. Erysiphe graminis DC. 
mittelstark 
stark 
stark 
Verf. rät an, jedesmal bei Bastarden die Empfänglichkeit gegen 
parasitäre Pilze genau zu prüfen. Matouschek (Wien). 
REED, H. S. and COOLEY, J. S., The effect of Gymno sporangium 
on the transpiration of Apple trees (Virginia Agr. Exp. Stat. 
Rept. [1911/12] 1913, 82—90; fig. 1). 
By the use of a specially devised apparatus which did not necessitate 
the removal of the leaves from the trees it was found that Apple leaves 
affected with Rust transpire less than healthy leaves. This result is 
opposed to an observation by Blodgett for leaves attacked by Gymnoconia 
interstitialis. In the case of this form, however, the lower epidermis is 
