768 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



Chlorosis, A Cure for. By Mokrzecki (Gard. Chron. No. 890, 

 p. 36, figs. 17 and 18; Jan. 16, 1904). — Hitherto there has not been 

 any cure for this disease, but the author claims to have found one. He 

 says : " It is a well- established fact that chlorosis in plants is due to the 

 lack of iron, and for the purpose of cure a certain amount of green 

 vitriol (iron sulphate) was introduced into the soil ; with the solution of 

 these salts the leaves were sprayed, and in the autumn cuttings and steins 

 were smeared with it also. But all these efforts gave only partial results, 

 as the cure was not always secured." It appeared that a sufficient amount 

 of iron was not absorbed by the trees by these methods, so " I bored from 

 one to four holes 1-1 1 centimetre in diameter, and deep enough to put 

 from 4-12 grammes of sulphate of iron ; these holes were smeared over 

 with cement." The wounds heal rapidly, and the ascending sap carries 

 the solution up to the leaves, in which the green colour soon begins to 

 appear. Other salts of iron, such as the phosphate and chlorate, do not 

 effect the cure so readily. " By this method I have effected a permanent 

 cure in. many hundreds of trees, of different varieties, not excepting 

 coniferous and evergreen trees." — G. S. S. 



Chocho, The. By A. F. F. Somerville (Agr. Gaz. N.S.W. pp. 835, 

 836, September 1904). — Chochos are about 5 inches long, Pear-shaped, 

 having a very rough, prickly skin, pale yellow in colour, though there is a 

 green variety. They may be purchased for Id. to Sd. each in Sydney, and 

 one plant will supply the wants of any one family, provided it is put into 

 good soil and gets plenty of water. Two fruits are enough to make a dish 

 for four persons, and they can be boiled or baked. The writer had a 

 chocho vine two years old which carried at the end of May 300 fruits. 

 The chocho is cultivated in some countries for its tubers and fruits, the 

 former growing to a size of a good Yam, which they resemble in flavour. 



H. G. G. 



Chromosomes, The Bivalence of, after Numerical Re- 

 duction, as Indicated by their Rotation in the " Matura- 

 tion " of the Animal Ovum. By J. P. Lotsy (Flora, xciii. 1904, 

 pp. 65-86 ; 19 cuts). — The numerical reduction in chromosomes in the 

 male and female primitive reproductive cells " gonotokouts," in which half 

 the somatic number of chromosomes makes its appearance, is probably due 

 to the union 2 and 2 of the chromosomes, one from either parent in each 

 pair. The separation of these (as postulated by Mendel, de Vries, Weis- 

 mann, Haacke, and others) is effected by the transverse separation in the 

 final mitotic division which divides the mature egg (oosphere) from its 

 abortive sister, the second polar body. — M. H. 



Chromosomes : Their Individuality in the Vegetable King- 

 dom. By O. Rosenberg (Flora, xciii. 1904, pp. 251-259 ; 7 cuts). — 

 In the cells of Capsella, Zostcra, Calendula the number of pseudo- 

 nucleoles is constant and identical with that of the chromosomes of the 

 species, so that these bodies appear to be permanent centres in the 

 "resting" nucleus, which is in function active, for the formation of 

 the chromosomes when it passes into kinesis. An amoeboid condition of 

 the nucleus is noted in the trophic cells of the suspensor of Capsella, with 



