331 
ammonia-ferments are decomposed with SEROR of ammonium- 
carbonate. The saltpetre bacillus then con s the ammonium- 
carbonate (and probably also amides) into eee i.e., into the 
best form of nitrogen plant-food. 
Unfortunately the whole of the nitrate thus formed is never 
available for plants, on account of the destructive action of the 
nitrate-destroying bacilli, which decompose the nitrates with 
evolution of free nitrogen, and so complete the nitrogen cycle. 
The nitrate destroyers are usually present in stable-manure, 
and cause a deplorable loss to agriculture, amounting in Germany 
to a sum of several million pounds annually. 
Efforts which, as Professor Maercker assured the German 
Chemical Society are Ard to meet with success at an early date, 
are being made to avoid this loss; and for this eae special 
bacteriological investigations are soe being conducted at many 
agricultural stations in Germany. 
DCXXXIIL—IMPROVEMENT OF SUGAR-CANE BY 
CHEMICAL SELECTION. 
The Kew oe Em 1894 (pp. 86-96) contained an account 
of the experiments made in Louisiana for the improvement of the 
sugar-cane by A nac Ne te of “seed canes,” t.e., of ER canes 
used for propagation. The principle was essentially the same as 
that which has been applied to the improvement of the Some pU 
(see Kew Bulletin, 1897, pp. 317, 318). The method has begun 
to attract some attention in sugar-growing colonies. The follóiine 
remarks are quoted by the Queensland Sugar Journal and 
Tropical Cultivator for April 15 last from Mr. McCulloch, ei 
Government Inspector under the Sugar Works Guarantee Act : 
zd aaa the improvement of our canes or the propaga- 
tion of new varieties by mean ine d or otherwise is a slow and 
iis process, pem we are, Teas debarred from individually 
impro r varieties by this means. This being so, we should 
give careful attention to accidental kae which undoubtedly 
do occur. In most canefields a stool, or stick of cane in a stool, 
is Non found having characteristics ds unlike in appearance 
to the mother plant. These a bd as * sports,’ or accidental 
T Where observed these nes should be carefully 
oted and used for future planting, “keeping them in a field, or 
ese of a field, by themselves. Then, again, one can almost always 
notice in a cane efield a few stools or sticks far and away cleaner, 
healthier, and bigger-looking than the others. These, at should 
be carefully noted and used for future planting. This s known 
as ‘seed selection.’ It is by such means as these, also by careful 
and intelligent cultivation, drainage, manuring, &c., by observing 
be bates dant ai of the soil to the plant, carefully recording the 
n it was planted, the cultivation bestowed on it, the manner 
of 8 stooling, number of canes in a stool, that every individual cane- 
grower in Queensland can do his little or more to better the 
