AGEICULTUKAL BOTANY. 329 



The practice of agricultural bacteriology, F. Lohnis {Landwirtschaftlich- 

 hakteriologisches Praktikum. Berlin, 1911, pp. VII +156, pis. 3, figs. JfO). — This 

 book is intended to give a basis for investigations and demonstrations in agri- 

 tural bacteriology. An introduction to bacteriological technique is given cover- 

 ing work in the bacteriology of air, water, and feeds; of milk, butter, and 

 cheese; of various fertilizing materials; and of soils. The appendix contains 

 a key to common species of bacteria and practical suggestions for the lab- 

 oratory. The work concludes with an index. 



One thousand American fungi, C. MclLVAiJfE and R. K. Macadam, revised by 

 C. F. MiLLSPAtJGH {Indianapolis, 1912, rev. ed., pp. XXIX+749, pis. 11, figs. 

 iUf). — This book gives descriptions of about 1,000 species of toadstools, mush- 

 rooms, and other fungi, with notes on their distribution, habitat, poisonous or 

 edible qualities, etc. Chapters are also given on toadstool poisoning and its 

 treatment, recipes for cooking and preparing mushrooms for the table, raising 

 nuisbrooms, etc. 



Seeds and plants imported during the period from April 1 to June 30, 

 1911: Inventory No. 27 (f7. S. Dept. Agr., Bur. Plant Indus. Bui. 242, pp. 

 99). — This inventory gives the usual data relating to seeds and plants intro- 

 duced by the Office of Foreign Seed and Plant Introduction during the period 

 indicated. About 900 numbers are included, much of the material having been 

 collected by F. N. Meyer in western China. 



Deciduous rootlets of desert plants, W. A. Cannon (Science, n. ser., So 

 {1912), A'o. 903, pp. 632, 633). — A study of the roots of many perennials and a 

 few annuals in the vicinity of Tucson, Ariz., showed that they have two sorts 

 of rootlets, which have similar functions but usually an unlike fate. 



A description is given of the root system of a desert shrub, Franseria del- 

 toidea, in which, it is stated, the superficial roots bear, in addition to the usual 

 type of rootlets, numerous adventitious rootlets in groups of about one-half 

 dozen. These are formed during the moister season of the year and die during 

 the succeeding dry period, seldom, if ever, persisting to form permanent roots. 

 They are designated by the author as deciduous rootlets, and it is assumed that 

 they are r^rhaps the first absorbing organs to function after the beginning of 

 the rainy season. The rapid formation of these rootlets increases enormously 

 the absorbing surface of the plants without increasing the distance of water 

 transport. The importance of this in the physiology of the plant is quite 

 evident. Nearly all perennials examined as well as some annuals exhibited a 

 somewhat similar condition. 



Setting of fruit and seed by cultivated plants, E. Zacharias (Ztschr. Bot., 

 3 (1911), No. 12, pp. 7S5-795). — The author discusses some of the factors opera- 

 tive in the setting of fruits and seeds by plants under cultivation and the trans- 

 missibility of characters acquired during this process. Among such factors the 

 following are mentioned: (1) Stimulation due to rubbing of stamens by insect 

 visitors, declared to be necessary to the production of pollen in some plants ; 

 (2) the stimulating effect of pollen from a different plant of the species, car- 

 ried by insects or wind; (3) a proper balance between vegetative and repro- 

 ductive activity; and (4) the relations existing between graft and stock. De- 

 generation and other aspects of heredity are also discussed. 



Low temperatures with exclusion of air and viability of seeds, Clemens 

 (NaturiD. Ztschr. Forst u. Landiv., 9 (1911), No. 9, pp. 402-409) .—The authot 

 investigated seeds of the fir, pine, cypress, oak, beech, maple, and ash. Th« 

 seeds were divided into two series, of which one was kept from the air at a 

 temperature of from 2 to 3° C, the moisture and carbon dioxid being removed 

 as formed. Those of the other lot were kept in a dry room, subject to vari- 



