278 Pflanzenkrankheiten. 



Hyphen schnüren sich „Konidien" ab, doch nicht in Reihen, sondern 

 sie entstehen durch Hefesprossung. Vielleicht dienen sie den Larven 

 zur Nahrung. In älteren Gallen fehlen die Anschwellungen an den 

 Hyphenenden, die Hyphen sind schwarzbraun und entwickeln Sporen. 

 Die Larve besitzt als Schmarotzer Chalcidier. Chaerophylhim bidbo- 

 sum in der Nachbarschaft trug nie die wohl neue Galle. Aehnliche 

 Ambrosiagallen sah Verf. aber auch auf Pastiyiaca sativa. 



Matouschek (Wien). 



Jackson, Fi. S., A new pomaceous rust of economic im- 

 portance, Gvmnosporangium Blasdaleanum. (Phytopatholog5^ 

 IV. p. 261-270. 1914.) 



A great number of experiments were made by the writer to 

 studj'' the relations between Gymnosporanghnn Blasdaleanum (Dietel 

 and Holway) Kern from Heyderia decurrens (Torr.) K. Koch {Libo- 

 cedviis decurrens Torr.) and many aecidial forms on pomaceous 

 plants. The aecidial form, originally described by Dietel and 

 Holway from northern California on Crataegus rivularis Nxitt. 

 and Ainelanchier alnifolia Nutt., has since been reported by Kern 

 as occurring on the latter host and A. ßorida Lindl. from Oregon 

 and on A. pallida Greene from California and C. Douglasii l^indl. 

 both from California and Oregon. The following hosts should 

 in the opinion of the writer be recorded as new for this species: 

 Cydonia vulgaris L., Malus Malus (L.) ßritton, M. rivularis (Doug.) 

 Roem., Malus rivularis X ^- Malus (natural hybrid), M.floribuiida 

 Siebold, Pyrits communis L., Sorbus spuria Pers., 5. sambucifolia 

 Roem. (?) and as collected by Godfrey, also Cydonia japonica Pers. 

 Based upon the results of his cultural experiments and upon the 

 morphological characters of the aecidia the writer believes the form 

 studied on all the hosts mentioned is the aecidial form of Gymno- 

 sporangium Blasdaleanum. 



The writer denies the opinion, held by all systemasists about 

 the telia of G. Blasdaleanum as developing from an annual mx'ce- 

 lium. "Witches' brooms" were found to be very abundant. In fact 

 they were always observed to occur on old trees affected with G. 

 Blasdaleanutn. The leaves of these were always found to be abun- 

 dantly covered with the characteristic telia of fungus. Mycelium 

 was alwaj's present in the tissues; in the older parts of the "wit- 

 ches' brooms" the mycelium ist most abundant in the pith. "Wit- 

 ches' brooms" were found in all stages of development and always 

 covered with telia. The}^ may reach a large size, sometimes two 

 feet in diameter. M. J. Sirks (Haarlem). 



Küster, E., Ueber die Gallen der Pflanzen. Neue Resul- 

 tate und Streitfragen der allgemeinen Cecidologie. 

 (Fortschr. naturwiss. Forschung. VIII. p. 115— löO. 27 Fig. Wien, 

 Urban & Schwarzenberg, 1913.) 



Die Gruppierung des Themas ist folgende: Gallen und gallen- 

 ähnliche Gebilde; Begriffsumgrenzung, die gallenerzeugenden Or- 

 ganismen, die äussere Gestalt der Gallen (organoide Gallen, Zellen 

 und Gewebe der Gallen), Aetiologie der Gallen (Vergleich der 

 Gallen mit pathologischen Gebilden ^anderer Art, Anomalien infolge 

 abnormer Ernährung, Wundgewebe, abnorme osmotische Verhält- 

 nisse), Gallen und Carcinome. Berücksichtigt wurden hiebei nament- 

 lich jene Daten und Resultate, die in dem Werke des Verfassers : 



