CURRENT LITERATURE. 
BOOK REVIEWS. 
: Photomicrographs of plant rusts. 
THERE is a difficulty in studying microscopic fungi, from which the student 
of phanerogamic plants is exempt. It arises from the minuteness of the parts, 
making it necessary to prepare a slide and place it under the microscope, and 
sometimes more than one slide, before the essential characters can be seen. As 
only one slide can be examined at a time, the student must carry a mental picture 
of the various forms previously examined which he desires to compare with the 
one under examination. He cannot lay his two or more objects side by side and 
have them both or all equally under consideration at the same time. 
One of the best known means for reducing this difficulty to a minimum is 
the use of photomicrographs. When skilfully prepared under uniform con- 
ditions and magnification they are of great assistance in making close comparisons 
between a few forms, and immensely facilitate the rapid review of a large series. 
Recognizing these facts, together with the additional one that many species 
are so rare that the student can not hope always to secure a specimen, Professor 
E.W.D. Hotway, of the University of Minnesota, has undertaken to publish a 
complete series of photomicrographs of the spores of the North American rusts.’ 
The work starts out with the genus Puccinia, taking the species up systematically 
according to hosts. The first number begins with the order Ranunculaceae, 
having seventeen species, followed by nine other orders. The 45 species of this 
first number are illustrated by 62 figures, all but one representing the spores as 
seen in the field of a microscope under a magnification of 250 diameters. — The 
Photogravure plates show almost the same perfection of detail as the original 
tographs, both being of superior quality. 
The text accompanying the plates is of the nature arate 
Species is fully described, with synonymy, distribution, and citation of cana 
€ work is all founded upon the specimens and treatises in the herbarrum of 
the University of Minnesota, and is carried out with much critical insight. 
€ number forms a highly valuable addition to the literature of the plant 
Tusts, and especially so on account of the illustrations, few botanists having such 
skill in the production of photomicrographs as the author.—J. C. ARTHUR. 
of a monograph. Each 
Luther Burbank. 
Tost who know Mr. Burbank personally admire hi 
acter; they who know his work acclaim him as a gentus 
i 
re his gentle and simple 
in plant breeding 
; Horw ay, E. W. o. North American Uredineae, Vol. I, part 1. 4to- PP iii+ 32- 
Pl. t-z0, Minneapolis, 1905. $2.00. 
1905] 459 
