BOTANY. 777 



Antlioxantlium odoratum, Agrostis vulgar in, Briza media., 3.nd. Alopecurus 

 geniculatus. Grou]) 3, Rolcus lanatus, H.molUs, Bromns mollis, Agrostis 

 canina, and Festuca ovina. Group 4, Molinia ccenilea, Aira ccespitosa^ 

 A. Jlexuosaj Siellngia. decumbenSj tardus stricta, and Phragmites com- 

 munis. 



The author has repeatedly tried the above method and considers 

 it much more reliable than any other. The practical application of 

 such an analysis the author considers under 6 heads: (1) Influence of 

 fertilizers and differences between first and second cuttings; (2) a 

 knowledge of the local differences in meadows as bearing on ameliorat- 

 ing conditions; (3) ability of different species to form aftermath, and 

 variations in the same; (4) classification of grasses according to their 

 ability to produce leaves and the causes which influence leaf develop- 

 ment; (5) the determination of seed mixtures adapted to certain con- 

 ditions, and (6) investigation of meadow plants according to their 

 nutrient material, the valuation and duration of meadows and of the 

 meadow land itself. 



Contributions from the U. S. National Herbarium, J. ]S^. Eose 

 [U. 8. Bept. Agr., Division of JBotanp, Contributions from the U. S. 

 National Herharium, vol. J, No. 9, pp. 393-434, pis. 13, figs. 10). — A 

 report is given, containing critical notes and descriptions of new 

 si)ecies, of a collection of plants made by E. Palmer in the States of 

 Sonora and Colima, Mexico, during the years 1890 and 1891. The 

 grasses were determined for this report by the late G. Vasey, the ferns by 

 D. C. Eaton, the Cyperacece by N. L. Britton, the species of the genus 

 Piper by C.de Candolle, the Sapindacew by L. Radlkofer, and assistance 

 was given by others in various groups. An index of this completed 

 volume is given in this number. 



The influence of cold on plants — a resume, 0. Abbe. — In 1888 and 

 1891 SebastianoCavallero ^ published his original investigations confirm- 

 ing the results arrived at by German students a few years before as to the 

 effect of frost upon plants. He states that until lately it was supposed 

 that by the freezing of the sap the cells are distended and the tissues 

 torn asunder, and that to this injury the death of the plant must be attrib- 

 uted. In the winter of 1887-'88 he ascertained that the frozen tissues 

 did not suffer any injury, and repeated his observation in 1890-'91. 

 He found that under tlie action of frost a rupture of the tissues is very 

 rare and that the cells themselves never freeze; that the small crystals 

 of ice are not formed within the cells, but in the intercellular spaces; 

 and that this formation occurs both in the hardy and the delicate plants. 

 It is the chemical changes brought about by frost that are of principal 

 importance. So far as it goes Cavallero's work confirms that of Miiller- 

 Thurgau, published first in 1880, and subsequently elaborated and 

 published in 1886. As his conclusions are not yet found in the text- 

 books, it may be stated that in general as the temperature of the plant 



iQior. Agr., 1888, Mar. 11; Gaz. Mantova, 1891, Jan. 24. 



