226 EXPEKIMENT STATION KECORD. 



descrilx^-d in language as nontechnical as the subject will admit; and as a fieldbook 

 the compactness of the volume, conciseness of the descriiitions, and excellence of the 

 illustrations make it easy to identify many of the more common species of wild 

 flowers. The absence of any key to orders and genera may prove detrimental in 

 the estimation of some, but through the pojiular instruction in nature studies many 

 plants are known by their family affinities, and this work will be found valuable in 

 supplementing the other studies. 



Tlie cultivated guavas and their botanical differences, J. B. Davy {Cali- 

 fornia Sta. Rpt. 1899-1901, j^t. 1, 2>p. 86-88). — In view of the increasing interest which 

 has been shown in the cultivation of guavas, the author has prepared a brief account 

 of the botany and economic uses of the genus, together with a key of the species 

 already introduced, by which they may be readily distinguished. Five species are 

 described in considerable detail, the classification given being based on differences 

 of the branchlets. A number of other species are mentioned which are insufficiently 

 known, and notes given on others which might j^robably prove serviceable in plant- 

 breeding experiments. 



Some Australian vegetable fibers, J. H. Maiden {Agr. Gaz. Nc'iv SurUh Wales, 

 13 {1903), No. 2, jjp. 167-182). — A list is given of some of the more important Aus- 

 tralian fiber plants, together with notes on their distribution and economic value. 

 The different plants are grouped according to orders. 



The Geastrse, C. G. Lloyd {Cincinnati: Aufli.or, 1.902, pp. 44, ,fi</s. 80). — A descrip- 

 tion is given of the Geasters, in which different parts are defined, and a classification 

 of the genera and species is given. Two genera are recognized — Myriostoma, with 

 1 species, and Geaster, with 22 species. 



The origin of species by mutation, D. T. MacDougal {Torreya, 2 {1902), Nos. 

 ^, pp. 65-68; 6, pp. 81-84; 7, j)p. 97-100). — An extended review is given of the f)rigin 

 of species by mutation, the theory and experiments of de Vries being described at 

 considerable length (E. S. K, 18, pp. 324, 619). 



The rheotropism of roots, F. C. Newcombe {BoL Gaz., 3.1 {1902), Nos. 3, pp. 

 177-198; 4, 2jp. 263-283; 5, pp. 341-362, figs. iJ).— The results of investigations of the 

 rheotropic movement of roots, as shown by the examination of 32 species of plants, 

 are given. These 32 species include all plants but 2 that have been examined for 

 rheotro])isni, and of the 34 that have l)een studied, 20 showed positively rheotropic 

 movements and 14 have been found insensitive. It is conclude<l that rheotropism 

 can not, therefore, be said to be a general phenomenon. 



The transformation of proteids during germination, G. Andre ( Compt. Rend. 

 Acad. Sci. Paris, 134 {1902), No. 17, pp. 995-998). — Results of investigation3 in 

 determining the transformation of proteids during the germination of beans are given. 

 Of the proteid materials which enter into the seed, albumin disappears most quickly. 

 Legumin, which represents about one-fourth of the total nitrogen of the unsprouted 

 seed, diminishes rapidly but never completly disappears, The amid nitrogen, such 

 as aspai'agin, etc., remains in solution after the separation of legumin and albumin, 

 and increases with the process of germination, so that the nitrogen, which is aliout 

 4.2 per cent of the total nitrogen of the seed, increases to more than 55 jier cent dur- 

 ing germination. The proteid materials which are insoluble in water form the greater 

 portion of tlie substance called conglutin by Rittenhaus. At the time the total 

 weight of the plant is about that of the seed, or when the plant begins to take up 

 nitrogen from the soil, the insoluble nitrogen increases rapidly, and this period is 

 characterized by the formation of new albuminoids. These, on the one hand, are 

 formed from the nitrogen taken from the soil and on the other by the conversion of 

 the soluble amids ami albuminoids. 



Observations on transpiration, C. C. Curtis {Bui. Torreif BoL Gluh, 29 {1902), 

 No. 6, })p. 360-373). — An account is given of the variation of the transj^iration due to 

 differences in electric illumination, moisture, cuticular and intracellular transjiira- 



