BOTANY. 421 



The ferment pectase acting- upon pectin also gives pectic acid. By 

 hydrolysis the pectic bodies yield pectoses, and especially arabinose. 

 By oxidation they yield mucic acid. From this it is concluded that 

 pentosan and galactan are present in the molecule of pectic bodies. 



It is claimed that the investigations of the author, as well as all 

 recent work, indicate that the pectic bodies are formed by the chlo- 

 rophyll of the plant. 



On the hybrid fecundation of the endosperm of maize, H. de 

 Vries {Rev. Gen. Bot, 12 {1900). JVo. 1S6, pp. 129-137,2)1. 1).—K 

 review of some of the literature bearing upon the immediate effect of 

 pollen, or xenia as it has been called, is given, together with an account 

 of the author's experiments with maize. The experiments are fully 

 discussed and the conclusion reached that the effect commonly noted 

 as the result of crossing different races or varieties of maize is due to 

 double fecundation. Wherever a grain of corn shows the character- 

 istics of the male parent in the endosperm it is the result of hybrid 

 fecundation. Where the characteristics of the female parent are 

 exhibited it is a case of self-fertilization. The explanation of these 

 phenomena is to be found in the discovery of double fecundation by 

 Nawaschin and Guignard. 



Progress of plant breeding in the United States, H. J. Webber and E. A. 



Be8sey ( V. 8. Dept. Agr. Yearhonk ]Sn9, pp. 4(15-490, pis. ■i,fi{/s. ^).— The early horti- 

 cultural and agricultural conditions of the United States are described, together with 

 early methods of plant breeding. The improvements effected during the past cen- 

 tury are mentioned more or less in detail, being grouped under the different headings 

 of fruits, berries, vegetables, cereals, ornamentals, nuts, cotton, etc. 



Progress of economic and scientific agrostology, F. Lamson-Scribner ( U. S. 

 Dept. Agr. Yearbook 1899, pp. 347-SG6, /zV/.v. 5) . —The early investigations relating to 

 grass and forage plants are briefly described, together with a description of the estab- 

 lishment and work of the Division of Agrostology of this Department. The grass 

 investigations which have been conducted in different parts of the country are out- 

 lined and descriiitions given of some of the more valuable grasses and forage plants. 



Economic grasses, F. Lamson-Scribner (K 8. Dept. Agr., Division of Agrostology 

 Bui. 14, rev., pp. 85, pis. 3, figs. 91). — This bulletin, which is a revised edition of a 

 previous one (E. S. R., 10, p. 718), contains much of the economic information given 

 in Bulletin 3 of this Division (E. S. R., 8, p. 687). 



Seedling forms of New Zealand phanerogams and their development, L. 

 Cockayne (Trans, and Proc. New Zealand Tnst'., 31 [1898), pp. 354-398, j)ls. .5). — A 

 biological study of a large number of seedling forms of New Zealand plants. 



The mistletoe, J. Huberty (Bui. 80c. Cent. Forst. Belg., 7 [1900), Nos. 4, pp- 284- 

 290; 5, pp. 373-381; 6, pp. 443-451) .—The life history of the mistletoe is reviewed 

 at considerable length, and its method of attacking the host and the effect, as shown 

 by analyses of the wood of infested and sound ti-ees, is described. Various means 

 of destroying mistletoe are suggested, among which the cutting away of the branches 

 is prol)ably the most efficient. 



Photometric investigations in vegetable physiology, Wiesner {Bot. Centbl., 

 82 (1900) , No. 10-11, pp. 316-318) . — A summary is presented of the author's inves- 

 tigations on the various adaptations of plants to light in the arctic regions. 



Formation of oil in the olive, G. Spampani {Bui. Soc. Bot. Ital., 1899, pp. 

 139-143; abs. in Jour. Roy. Micros. 8o<;. {London'], 1900, No. 3, pjj. 342, 343).— A 



