No. 376) REVIEWS OF RECENT LITERATURE. 2QI 
dullest on the steamed turnip, where there was also a marked pro- 
duction of the brown pigment. The organism was also grown in 
fermentation tubes using the various kinds of sugars. Itis not an acid 
or gas producer. A brief summary of characters is given at the end 
of the paper. The organism is closely related to Wakker’s Bacterium 
Ayacinthi, from which it differs chiefly in its pathogenic properties. 
This paper is an important contribution to our knowledge of bacterial 
diseases of plants. Great care was observed in details of making 
media, and the manner in which the infection experiments were 
conducted should be highly commended. 
In a second paper on the same subject’ Dr. Smith deals largely 
with methods of prevention, giving the result of field studies made 
in 1897. Nine-tenths of the infections are through water pores. 
Infections by means of the gnawings of insects were also observed. 
The disease has been successfully inoculated into the black mustard, 
and is common in some places on charlock. No evidence has been 
obtained to show that it is transmitted by seed. A contaminated 
soil is the most frequent source of infection. The observations here 
recorded leave little room to doubt that the organism lives over 
winter in the soil, that it is often transplanted from contaminated 
soil to healthy fields in diseased seedlings, and that the preparation 
‘of healthy seed beds, że., on soil free from this organism, is one of 
the most important preventive measures. Of course, rotation of 
crops would also be an effective remedy. T. BH. PANNE 
A New Laboratory Manual.— To the many laboratory manuals 
is added a new one in the field of botany,’ which is intended to give 
the student a general view of the subject and at the same time to lay 
a foundation upon which more advanced studies may be built. The 
author suggests that the rather extended scope of the book need not 
prevent its use for briefer courses, since by judicious selection certain 
parts only may be used where the entire field cannot be covered. 
One hundred and ninety-one illustrations add to the attractiveness of 
the book, and in the main they are well selected from good sources. 
Though the illustration of a laboratory guide is a device for convey- 
ing information rather than promoting independent investigation, it 
is by no means certain that it is a reprehensible practice when, as is 
1 The Black Rot of the neg Farmers’ Bulletin, No. 68. U.S. Dep. of 
Gigi Washington, D. C., Jan. 8, 18 
"C. H. Clark, A Labor Ay anyal in Practical Botany. New York, 
American Book Company (1898), 271 pp. 
