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attacked by thirty-six diffeient species of Glomerella, it has been 

 found that neither morpliological nor physiological differences 

 can be observed v/hich are sufficiently constant to be regarded as 

 specific characters. All the different forms have been referred 

 by the authors to three species of Glomerella : G. cingiilata which 

 occurs on thirty- four of the hosts, G. gossypii on one (namely, 

 cotton), and G. lindcmuthianum, on one. 



G. cingiilata is exceedingly variable in all its characters. The 

 cause of this variability is not yet clear. The essential point about 

 this fungus is that it can often be found to grow from apparently 

 healthy tissue, which has been washed in corrosive sublimate. 

 The explanation is that the chlamydospores send a germ tube 

 down through the epidermis of the host plant, which lies quiescent 

 until the plant becomes weakened from some physiological cause, 

 when the fungus begins to develop as a vigorous parasite. 



It is stated by the authors : "Inoculation experiments with 

 fruits have shown that most of the forms from different hosts 

 will produce the characteristic Glomerella rot on fruits of other 

 hosts. It is also shown that there is a great variability in the 

 virility of different races or strains of ihe fungus from the same 

 host. In one experiment races from the lemon, grape and fig 

 produced more serious cases of bitter-rot of apple than a race of 

 the fungus derived from apples. These facts are of great im- 

 portance in connection with tlie selection and production of dis- 

 ease-resistant varieties of plants." 



It may be added, further, that this is of immense importance 

 in regard to mycological legislation, in view of the fact that the 

 disease can apparently spread as easily from temperate countries 

 to the tropics, as within the tropics itself. It must also be remem- 

 bered that G. cingnlata can also be carried by any one of thirtv- 

 four different species of agricultural plants, including such 

 diverse forms as palms, oranges, apples, gooseberries, cacao and 

 arrowroot. Of great economic significance is the fact that one 

 species of Glomerella is confined to cotton. This species, it may 

 be added, occurs in the West Indies and causes the well-known 

 disease, anthracnose. 



The production or non-production of the perithecial stage of 

 Glomerella appears to be a fairly well-marked hereditary race 

 character. There is no evidence to show that the production 

 of perithecia is controlled by any of the ordinary conditions of 

 nutriment or environment, though accurate investigation along 

 this line would possibly lead to results of great importance. 



In conclusion, the methods of controlling Glomerella may be 

 briefly summarized as follows: (1) spraying with Bordeaux mix- 

 ture; (2) selection of fungus-free seed — particularly valuable 

 in the case of cotton; (3) eradication and destruction of dead 

 and diseased parts of .infected plants. 



The selection and breeding of resistant varieties may also be 

 practicable in some cases. — Agricultural Nczvs. 



