30 GENETICS [Bot. Absts. 



FOREST BOTANY AND FORESTRY 



Raphael Zon, Editor 



211. Fischer, Cecil E. C. Forest grazing and the Nellore "Kancha System." Indian 

 Forester 44: 531-537. Nov., 1918. — Cattle have severely injured the forests in the Nellore 

 district, and regulations provide certain blocks to be grazed under lease, a deferred system 

 being used. The aim is for communal grazing and communal forest protection. The conflict 

 of grazing and forestry is recognized, and areas are divided into forests and fuelwood areas, 

 and grazing lands. On the latter, all the timber of value will be removed and logging will be 

 done to encourage forage and to discourage forest reproduction. By these operations, it is 

 hoped to evolve pure grazing areas studded with shelter trees, and capable of supporting more 

 cattle than at present. [Through Abst. in: Agric. Jour. India. 1918: 95-101. 1918.]— E. N. 

 Munns. 



212. Lee, Y. K. [Chinese.] The relationship of forestry to farming. Khu-Shou [Science, 

 a publication of the Science Society of China.] 4: 43^47. 1918. 



213. McCarthy, Edward F., and Raymond J. Hoyle. Production of pulp on balsam 

 lands. Paper 23 7 : 14-18. Oct. 23, 1918. — Data on a stand of balsam in the southern Adiron- 

 dacks, which shows accelerated growth for period of five decades. All growth data are ar- 

 ranged by age classes. Includes stand tables from samples and plot study of same area, 

 also two other stand tables from caliper records on swamp type in Adirondacks. Amount of 

 reproduction per acre under virgin stand is shown in a table.' — The study is chiefly interest- 

 ing as a suggestion of what will occur on swamp lands if fire is kept out. Authors predict 

 "that these lands may be expected to produce a cord of pulp per acre per year without 

 excessive care." — Edward F. McCarthy. 



214. Purvis, J. E. The conversion of saw-dust into sugar. Proc. Cambridge [England] 

 Phil. Soc. 19: 259-260. 1919. — Varying quantities of sawdust from ordinary deal, digested 

 with different acids of varying concentrations yield varying quantities of sugar, depending on 

 the nature of the acid, its strength relative to the amount of sawdust used, and the length 

 of digestion. — Michael Levine. 



215. Schwab, W. G. The forests of Tazewell County, Virginia. Office of State Forester, 

 Bull. 18. 14 p., 6 plates, 1 folded map. 1917. — These three counties are all in the extreme 

 southwestern part of the state, among the mountains, and contain a large amount of forest. 

 Taking the three together, the most important trees are several species of Quercus. Lirio- 

 dendron tulipifera, and Castanea dentata. The illustrations are from photographs showing 

 the various forest types and conditions of exploitation. — Roland M. Harper. 



GENETICS 



George H. Shull, Editor 



216. Allard, H. A. Gigantism in Nicotiana tabacum and its alternative inheritance. 

 Amer. Nat. 53:218-233. May-June, 1919. — Work of previous investigators on gigantism in 

 Nicotiana is reviewed and the independent origin of several different strains of mammoth 

 plants recorded. Giant or mammoth plants have appeared suddenly in commercial plantings 

 of the Sumatra, Maryland, Cuban and Connecticut Havana types of Nicotiana tabacum. 

 They also occur in varietal crosses of these types and are reported by the author in progeny 

 of a species cross between Nicotiana tabacum and Nicotiana sylvestris. — These giant plants 

 are found to differ from. the varietal type only in height and number of leaves. One of these 

 plants reached a height of nearly 5 meters and developed 123 leaves. The giant habit of 

 growth with its increased vegetative vigor delays blossoming to such an extent that seed can 

 be obtained only by transplanting the plants to the greenhouse. — Author gives analysis of 



