Botojiical Notes, 115 



A question at once arises as to whether this unusual external 

 appearance would also be accompanied by deceptive internal 

 records in the so-called "rings of growth." It is a well-known 

 fact that resumption of growth in the spring is accompanied 

 by a zone of woody tissue, containing at least larger water- 

 tubes and other elements of the xyjem, showing more open 

 construction, thinner walls, etc. We have examined cross 

 sections of this material and can say rather positively that 

 there is not as pronounced a difference between the various 

 layers added during the season as that usually found in the 

 regular rings of gro\^i:h. In some parts of a section there are 

 some fairly well marked rings, but in others there is little 

 to distinguish one part from another. A section might well 

 be termed characterless. This might be expected when one 

 considers the long-continued wet weather and coolness. Still 

 there was enough difference at times tc bring about retarda- 

 tion or cessation of growth, and then its recurrence. We 

 hope to be better able to judge as to the facts when we shall 

 have been able to secure twigs of what may be a more nearly 

 normal season. 



One peculiarity of the results this season is that some twigs 

 on a tree show the above-mentioned marks of cessation and 

 renewal of growth, while others do not. 



In connection with the subject we wish to add that, in our 

 opinion, a growing season with the usual spring and summer 

 attributes, followed by a wet fall with renewal of growth, 

 is more likely to disturb the annual markings than is one like 

 the past season. 



We conclude this, however, that outward appearances may 

 be definitely deceptive as to showing the age of a twig. 



r,. DATA CONCERNING THE DISSEMINATION OF WHEAT RUST 

 (PUCCINIA GRAMINIS PERS.) 



Puccinia graminis Pers. in its complete development has 

 five kinds of spores, as follows : spermatia, aecidiospores, ure- 

 flospores, teleutospores, basidiospores. This last kind is pro- 

 duced by the teleutospores in the spring. These infect the 

 young leaves of the barberry. The work of the spermatia is 

 not known. These and the aecidiospores are found on the bar- 

 berry. The latter infect the wheat. The fungus in the wheat 

 at first gives rise to uredospores, which infect more wheat and 

 thus spread the rust. Later the same mycelium produces the 



