3 22 



and by sowing seeds of that, forms exhibiting great vigor that would 

 breed true, could be picked out. 

 See also: 



A. HENRY. Elm Seedlings showing Mendelian Results. (Lin- 

 man Society, April 7, 1910); Notice in Nature, vol. 83, April 21, 1910, 

 P- 238. 



C. S. COOPER and W. P. WESTELL. Trees and Shrubs of the 

 British Isles, Native and Acclimatised. (In two volumes; 

 78 full-page plates by C. F. Newall. London, J. M. Dent & 

 Co., 1909). Reviewed in Nature, Vol. 83, April 28th, 1910, 

 p. 243. 



" The number of cultivated species of hardy trees and shrubs 

 now exceeds 3000, and it would be an impossible task to select 

 one-sixth of these for treatment and satisfy everyone." 



PERCY GROOM. Remarks on the Oecology of Coniferae. 



Annals of Botany. London, April 1910, vol. XXIV, n. XCIV, 

 pp. 241-269. 



The following extracts of this paper are of interest: 



" It is worthy to note that evergreen Coniferae have a larger 

 number of serious fungal and insect foes than have dicotylous trees 

 in north-temperate regions. This may be wholly, or only partially, 

 another method of stating the proposition that the Conifers are 

 more readily killed or injured. 



" To prove the statement I have drawn up lists of tree-attacking 

 Fungi and insects from the recognized textbooks on the diseases 

 of trees by Hartig, Von Tubeuf, and Judeich and Nitsche. 



" I give below a table showing the number of Fungi attacking 

 forest trees, first as given in Hartig's ' Diseases of Trees, ' and thus 

 as enumerating the ones that were so obviously important as to 

 be investigated first, and secondly, as given in Von Tubeuf s ' Di- 

 seases of Plants. ' In my lists I originally grouped fungal diseases 

 into four classes: 



1) Those fatal to the tree. 



2) Those severe, and causing much injury to the living tree. 



3) Those that are less severe, and may be merely leaf-diseases 

 from which the tree usually or always recovers. 



