142 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



in several cities in U.S.A. The descriptions are very full and contain 

 much interesting and valuable matter. 



The reports on vacant-lot gardening in Minneapolis and school 

 gardening in connexion with Utah State Normal Training School 

 contain many suggestions calculated to help a teacher to connect 

 his school gardening with home gardening. 



The report on Greeley, Colorado, contains a scheme of instruction 

 for teachers in Nature Study and Elementary Agriculture. 



The diagram on p. 38, showing the relation of soil to living, is 

 extremely good and worth copying. — W. W. 



Chinese Cabbage, Pe-Tsai, The. By S. Mottet {Rev. Hori. de 

 I'Alg. March 1913, p. 118). — ^A note taken from V Agriculture Nouvelle 

 on the Pe-Tsai {Brassica chinensis). This vegetable, which was intro- 

 duced into Europe as early as 1855, has been the subject of number- 

 less experiments and articles, but is little cultivated among us now- 

 adays. In the East, however, it occupies an even more important 

 place as an article of food than the descendants of the Brassica oleracea 

 do in Europe. 



The Pe-Tsai does not heart," and in appearance is really more 

 of a cos lettuce than a cabbage. It is eaten green, either cooked or 

 raw, in salads, and the advantages claimed for it are — early maturity, 

 quick development (which makes it possible to harvest a double 

 crop in the year), its comparative hardiness, and the fact that it may 

 be eaten at all stages of its growth. This allows of thick planting 

 and the utiHzation of all successive thinnings. — M. L. H. 



Chlorophyll, Constitution of. By Julius Stoklasa, Johann Sebaf, 

 and Emanuel Senft (Beih. Bot. Cent. xxx. Abt. i, Heft 2, pp. 167-235 ; 

 10 pi.). — In this important article Stoklasa maintains his views re- 

 garding the structure of chlorophyll ; the phosphorus which he 

 considers to be an essential element in chlorophyll becomes insoluble 

 in alcohol or ether if dried leaves are used. This explains the results 

 of Willstatter and others. Chlorophyll always contains from '14 to 

 1*54 per cent, of phosphorus (dry weight of the extract). He describes 

 also the chemical constitution of various chlorophyll extracts, some 

 obtained commercially and others from fresh leaves of nettle, grasses, 

 wheat, Tanaceium, Galeopsis, &c. 



He concludes that chlorophyll consists of three different sorts of 

 complexes : (a) Phaeophorb and metal groups soluble in alcohol and 

 ether ; {h) Phaeophytin, soluble in petrol ether ; and (c) Chlorolecithins, 

 which are unions of either of these with phospho-glycerides. Magnesium 

 is one of the above metals and accompanies phosphorus. 



The colour change of leaves in autumn is a hydrolytic breaking 

 up of chlorophyll with separation of ] haeophytin and phosphatides. 

 These are brown in colour, and allow the yellow and red of Xantho- 

 phyll and Carotin to appear. Lecithins are not combined, but 

 mixed with the chlorophyll. 



