9>^0 JOTTRNAL OF THF, ROYAL HOF.TTCITLTUKAL ROCTETV 



instructions for growing, harvesting, storing, and marketing onions in 

 Northern Indiana, where hundreds of acres are annually devoted to the 

 crop. The soil is mostly what the writers call black muck," and 

 the land has in most instances been reclaimed by draining the swamps. 

 This muck " consists almost entirely of organic matter, and usually 

 contains 2 or 3 per cent, of nitrogen, which, however, exists in a form 

 in which it is not available to plants, and as potassium is also gene- 

 rally deficient the soil requires suitable fertilizers to become fully 

 productive. 



The second bulletin contains the results of investigations undertaken 

 at the Agricultural Experiment Station of New Mexico as to the best 

 fertilizer to use for Spanish onions in that district. These tests showed 

 that sodium nitrate supplied twice at the rate of 600 lb. per acre pro- 

 duced the best results, and that the largest yields are to be had from 

 transplanted onions, though good crops may be raised from early field- 

 planted seed. — M. L. H. 



Orange, Sweet, A New {Jour. Soc. Nat. Hort. Fr. ser. iv. vol. xi. 

 p. 15; Jan. 1910). — Dr. Trabut has addressed a note to the ** Academic 

 des Sciences " on the subject of the hybridization of the Citrus. He 

 describes a new variety of orange named ' Clementine,' which is now 

 to be found in many orange gardens in Algeria, and which is a hybrid 

 between the Mandarin, Citrus nobilis, and Citrus Bigaradia. Con- 

 trary to the usual opinion, Dr. Trabut considers that the common sweet 

 orange Citrus Aurantium, was originally produced in the same way. 

 He has observed that the Citrus Bigaradia does not cross with the 

 sweet orange, but does so readily with the Mandarin, and this cross 

 produces hybrids of varying character, of which some bear a very close 

 resemblance to the ordinary sweet orange. On the other hand, so 

 many of the known forms of Citrus have been produced by fortuitous 

 crossing, that it is difficult now to tell the exact proportions of their 

 descent from any single primitive species. — M. L. H. 



Orchards : Protection from Frost by Smudg-e Pots. By H. M. 



Dunlop [U.S.A. Hort. Soc. Illinois, Trans. 1909, new ser. vol. 43, 

 pp. 117-125). — This method is beginning to be adopted in California 

 and Colorado, and consists essentially of an open metal vessel con- 

 taining wood shavings saturated with crude petroleum. The oil which 

 remains at the bottom of the pot after the shavings are consumed causes 

 a heavy smoke, and it can be arranged that this happens at the time in 

 the early morning when the frost is usually most severe. The prin- 

 ciple of warding off frost by a cloud of smoke is further discussed on 

 pages 325 to 331 of the volume above quoted, sawdust being the basis 

 of the system described there. See also abstract in the last number of 

 the Journal (p. 505) under the same head. — A. P. 



Orchards, The Care and Management of. By Owen Thomas 



(Garden, June 29, 1910, p. 52; Feb. 12. p. 82 ; March 12, p. 125; and 

 April 16, p. 188). — The writer is struck by the enormous loss of young 



