FIELD PROPS. 851 



Summarizing his Investigations, the author concludes thai tin* line previously 

 drawn between chlorophyll-containing plants and those containing no chloro- 

 phyll, based upon their ability to build up protoplasm and albuminous products 

 from simple solutions, can no1 be so sharplj held as for rly. 



The production of the differenl pig ats is described, and the influence of 



different media on pigmenl production is shown. Pyocyanin is formed where 



there is presenl a suitable corabinati >f carbon, hydrogen, oxygen, and nitro 



gen, together with some sail or salts to aid in the synthesis. For the formation 

 of fluoresced pigments both sulphur and phosphorus are essential. The produc- 

 tion of fluoresced pigments is favored by a high phosphate content and :i 

 slightly alkaline reaction. The red pigments of a number of species require the 

 presence of magnesium sulphate and a phosphate, preferably potassium phos- 

 phate. The rose-red pigments investigated are produced only in the presence of 

 lactic acid, while the yellow pigments of a number of species and ;i few red pig- 

 ments are formed very slowly in nonalbuminous media. 



The salts which favor the production of pigments are necessary, nol to render 

 the solution isosmotic, bu1 for the direct nutrition of the bacteria or to fix the 

 acids produced, which otherwise would have a toxic effeel on the bacteria. The 

 formation of pigmenl is dependenl upon the reaction of the media, suitable 

 ranges of temperature, and the free access of oxygen. Abnormal temperatures, 

 acid or alkaline media, and a lack of oxygen lead to a colorless growth. Besides 

 the pigments and albumin-like bodies the chromogenic bacteria form acids and 

 ammonia, winch apparently arise from the breaking up of asparagin or sugar 

 and are independent of pigmenl formation. The production of pigment, it is 

 held, is not .in essential, vital act. 



The author concludes with an extensive chronological list of publications 

 relating to the subject 



The mistletoes of caoutchouc, O. Warp, rr.r, {Tropenpflanzer, 9 (1!)":,), \>,. n. 

 />/>. 683-6^1, figs. 5). — Descriptions are given of species of Strutanthus, Phthi- 

 rusa, and Phoradendron which attack caoutchouc and also occur on a number of 

 other plants of economic importance in the Tropics. 



New pocket atlas on edible and poisonous mushrooms, P. DrMi'i: i Vouvel 

 atlas de /><>ch>- des champignons comestibles et ven£neux. Paris: /'. Klinck- 

 9%eck, 1905, />/>. Vl'-f //•'• pis. 6-4X. — Brief descriptions with colored illustrations 

 of 66 species of mushrooms. 



FIELD CROPS. 



Report of the experimentalist, < '. A. Zwrrz {Ann. T?pt. Ontario Affr. Ool. 

 and Expt. Farm, .11 {1905), pp. 165-221, figs. 9).— In a 1-year experiment with 

 12 varieties and classes of farm crops, common emmer stood firsl in average 

 yield of grain with 2.<;-_m lbs. per acre, Mandscheuri barley second with 2,616 lbs., 

 and Joanette oats third with 2,497 lbs. It is estimated that barley has aboul 12to 

 lo pci- cent of hull, emmer about 22 per cent, and oats approximately •■'.«» per cent. 

 The lowest yields of grain were secured from common irrass peas and common 

 spring vetch, the yields being 768 and 722 lbs. per acre, respectively. The adap- 

 tation of particular varieties of field crops to certain localities and soil condi- 

 tions is pointed out. 



The average results from l year's seed selection show thai large s 1 surpassed 



small seed by l'.u per cent for 5 grain crops, in.:: per cent.for rape, and 60J 

 per cent for 5 kinds of field roots. The average results ,,)' several years show 

 that plump seed of barley and wheal gave a yield of grain 20.2 per cent greater 

 than shrunken seed. Experiments conducted lor years with sound and broken 



