274 



In the October issue (page 236) Professor Macoun's address 

 was given as Ontario instead of Ottawa. 



Teachers in the southwestern states will be interested in The 

 Trees and Shrubs of San Antonio and Vicinity. This little book- 

 let gives the woody plants of the region, with a brief, non- 

 technical description, and a short paragraph on uses and habitats. 

 There is no key, but, as the author says, any plant may be traced 

 to the family by any general flora; and as the plants are grouped 

 by families, its further identification is a simple matter. The 

 common names are emphasized by being placed first. 



Professor Bessey {Science, November 11) has made a new 

 estimate of the number of species of plants "with which botanists 

 have enough acquaintance to permit of their systematic arrange- 

 ment and enumeration. The result is that roughly speaking 

 we may say that there are now known about 210,000 species, 

 distributed as follows: Myxophyceae (Blue Greens) 2,020, 

 Protophyceae (Simple Algae) 1,100, Zygophyceae (Conjugate 

 Algae) 7,000, Siphonophyceae (Tube Algae) 1,100, Phaeophyceae 

 (Brown Algae) 1,030, Carpophyceae (Higher Algae) 3,210, 

 Carpomyceteae (Higher Fungi) 63,700, Bryophyta (Mossworts) 

 16,600, Pteridophyta (Ferns) 2,500, Calamophyta (Calamites) 

 20, Lepidophyta (Lycopods) 900, Cycadophyta (Cycads) 140, 

 Strobilophyta (Conifers) 450, and Anthophyta (Flowering 

 Plants) 110,000. 



An article on conserving the purity of the soil {Science, Oct. 21) 

 by H. L. Bolley emphasizes the necessity of keeping soils, es- 

 pecially for cereals, in a sanitary condition. The author con- 

 cludes with the following paragraph : 



"If, on the other hand, you declare for careful seed selection 

 in all cases, careful seed disinfection at all times, the formation 

 of a well-aerated but compacted seed bed, and for as extensive 

 a rotation of crops of as wide-spread character as possible, you 

 of the new dry land regions of the west have the greatest possible 



