Bacteriologie. — Lichenes. 33 



Biffin, W., The growth of Leguminous plants and soll 

 inoculalion. (West Indian Bull. X. 1. p. 93—106. 1909.) 



The author gives a historical resume of the progress of our 

 knowledge of the subject, outlining the experimental work done by 

 Boussingault, and Lawes and Gilbert in the later part of the 

 nineteenth centur5^ and indicating the chief results obtained by the 

 more recent investigators right up to the present date, special refe- 

 rence being made to inoculation by nitro-bacterine and the work of 

 Professor Bottomley. W. Brenchley. 



Bottomley, W. B., Some Effects of nitrogen-fixing Bac- 

 teria on the growth of non-leguminous plants. (Proc. 

 Royal Soc. LXXXI. B. 548. p. 284—289. 1009.) 



Investigations showed that in all bacterial cultures prepared 

 from the algal zone of root-tubercles of cycads, taken from below 

 the surface of the soil, Pseudomonas radicicola was always associated 

 wich a species of Asotobacter. 



Experiments were subsequently undertaken to determine to 

 what extent, if any, this association of bacteria gave an increased 

 power of assimilating free nitrogen. The two bacteria were grown 

 both as pure and as mixed cultures, and the analytical results indi- 

 cated that Pseudomonas and Asotobacter together make a powerful 

 combination for fixation of free nitrogen. 



Further experiments were made to ascertain whether a mixed 

 culture of Pseudomonas and Asotobacter applied directly to the roots of 

 non leguminous plants would benefit their growth. Oats, Hyacinths 

 and Parsnips showed an increase in weight of the treated plants 

 over the untreated. In field tests made with Barley the grain 

 obtained from seed moistened with the mixed culture has a higher 

 nitrogen-content than that from untreated seed. W. Brenchley. 



Hall, A. D., The fixation of nitrogen by Soil Bacteria. 

 (Nature. LXXXI. 2043. p. 98. 1909.) 



This article is a criticism of Professor Bottomley's paper on 

 "Some Effects of nitrogen-fixing Bacteria on the growth of non- 

 leguminous Plants" (Proc. Roy. Soc. B. LXXXI, 1909, 284.). The 

 writer states that as the subject is one of far reaching interest, and 

 as the experimental differences obtained seem in many cases to fall 

 almost within the ränge of experimental error, more data are neces- 

 sary before the results can be accepted. Definite points are suggested 

 that need more explanation and more published figures. 



W. Brenchley. 



Zahlbruckner, A. , Vorarbeiten zu einer Flechten flora 

 Dalmatiens. (Gestern botan, Zeitschr. LIX. 1909. p. 315—321, 

 349—354, 398-407, 488—503 und LX. 1910. p. 13-22 und 71-81. 

 Mit einer Textabbildung). 



Die vorliegende Nummer dieser Beiträge ist bedeutend umfang- 

 reicher als die vorhergehenden. Sie enthält in erster Linie zum 

 grössten Teil die Bearbeitung der reichen lichenologischen Aufsamm- 

 lung, welche Stabsarzt Dr. A. Latzel in der näheren und weiteren 



Umgebung Ragusas, in der Umgebung von Metkovic und auf 

 der Sujcznica aufbrachte. Ferner fanden Aufnahme die Kollektion 

 I. Baumgartners von Chuso und Veglia, Dr. F. Vierhap- 



Botan. Centralblatt. Band 114. 1910. 8 



