100 The Plant World. 



the Asia-Alaskan and the Greenland-Laborador, may be desig- 

 nated. Arctic Europe is to be considered as the center of dis- 

 tribution of the Ktaadn alpine flora, and the glacial migration 

 was dominantlv bv the Greenland-Laborador route. 



The Mistletoe Pest in the Southwest is discussed by Prof. 

 William L. Bray in Bulletin No. 166 of the Bureau of Plant 

 Industry (1910). A list is given of thirty-two species of plants 

 which serve as hosts of the mistletoe in Texas. A curious habit 

 of the parasite is exhibited in the prevalence of infection upon 

 different species in different localities. Thus the sycamore, 

 upon which the mistletoe has not been reported in Texas, is one 

 of the most commonly infected trees in the river bottoms of 

 Arkansas, as it is also in Southern California. At San Antonio 

 and southwestward the mesquite is the chief mistletoe host, 

 while the water oak at Bryan, and the osage orange in north- 

 eastern Texas are specially subject to its attacks, and so on. 



Passing beyond the limits within which the author's obser- 

 vations were made, it is instructive to note that the mistletoe 

 family, as a whole, shows a progressive development of para- 

 sitism from the Australian Nuytsia, a non-parasitic tree, through 

 the "half parasitic" mistletoes of Europe and the United States 

 to the degenerate, absolutely parasitic Phrygilanthus aphyllus, 

 which lives on a species of Cereus in Chile. 



The MacMillan Company of New York (66 Fifth Ave.) 

 have recently issued a new "Manual of Gardening," by Prof. 

 L. H. Bailey, which is designed to be a practical guide to the 

 making of home grounds and the growing of flowers, fruits and 

 vegetables. In addition to a lucid discussion of various classes 

 of plants and their culture, treatment for disease, etc., in the 

 garden, lawn, and window garden, some valuable hints are given 

 as to the laying out of grounds and the execution of landscape 

 effects. The book is profusely illustrated and is probably the 

 best small handbook on the subject yet issued. 



In the Plant World for May, 1908, a resume was given 

 of the work of Dr. H. Winkler of the Botanical Garden at 

 Tuebingen, Germany, in producing forms that appeared to be 



