changes in temperature favor the development of rust in cereals but 

 usually this has been attributed to the indirect influence of cold in 

 causing a deposit of dew in which tin spores could L r <rinin;itc. In the 

 light of these experiments this explanation can hardly be the true one. 

 Spores which refused to germinate after lying in water several days 

 germinated readily after exposure to cold. It would seem as if the 



cold were capald< of Mimulatini: lh- spore- to germinate only when the 

 latter have been rendered receptive by exposure to rainy weather, but 

 further experiments and observations are necessary. It is at least cer- 

 tain that the spores of jEvidium bfrbrndi*, which germinated badly 

 after cooling, were gathered in dry weather, while those which germi- 

 nated abundantly after cooling were gathered (on three different occa- 

 sions) after several rainy days. The fungi tried by Dr. Eriksson were 

 .[iridium brrberidi*, Ae. rhamni, Ae. mage? 1 



strobi, Uredo glumarum, U. alchemilloz, U. graminis and U. coronata. 

 The original paper, entitled Ueber die Forderung der Pilzsporenkei- 

 mung durch Kiilte, may be consulted in Centralblatt fur Bakteriologie 

 und Parasitenkunde, Allg., Bd. I, p. 557.— Erwin F. Smith. 



Botany at the British Association. — The presidential address 

 of W. T. Thistleton Dyer before the new Section K (Botany) of the 

 British Association at the Ipswich meeting (Nature, Sept. 26, 1895) is 

 an exceedingly well written and interesting paper and one likely to 

 obtain a wide reading. It deals with such topics as the following : 

 Retrospect, Henslow, botanical teaching, museum arrangement, old 

 school of natural history, modern school, nomenclature, publications, 

 paleobotany, vegetable physiology, assimilation, and protoplasmic chem- 

 istry. The two and a half columns of sensible remarks on botanical 

 nomenclature are specially commendable to American readers, as also 

 what is said on teaching and in the last three topics of the address. 







printed texts should be so largely taking the place of the careful study 

 of plant phenomena in many English schools, the tendency in this 

 country of recent years being happily in the other direction.— Erwin 

 F. Smith. 



Nitrifying Organisms.— Messrs. Burri and Stutzer, of the agri- 

 cultural experimental station in Bonn, have discovered a bacillus (See 

 Centrb.f. Bah. u. Par. Allg., Bd. I, No. 20-21, 1895) capable of chang- 

 ing nitrites into nitrates and in many respects resembling Winograd- 

 sky's organism, but which grows readily in bouillon and on gelatine. 

 This bacillus is much larger than the measurements given by Wino- 



