>94 



Journal of Agriculture. 



[lo Mav, 1910. 



bracts (Fig. 3). The healthy cob is sur.rounded by a variable number of 

 leaves (in some cases I have counted 21) and these bracts, as they are 

 called, when surrounding the flower, are l:>urs.t by the swelling smut spores 

 and exposed to view. 



There is one interesting fact about smutted maize plants which is 

 worthy of mention and that is, that cows are very fond of them. I have 

 seen such diseased plants fed to milking cows and they greedily ate them 

 uj;, smut and all. They preferred them to the ordinary healthy maize 

 and there was often a struggle to get possession of them. I am assured 

 by a grower that he fed them to one milking cow without any injurious 

 effects, either to the animal, or its milk. The American Corn Smut, 



on the other hand, has similar properties 

 to Ergot, and it would be an interesting 

 sul>ject for investigation, if the Head 

 Smut affected cattle in a different manner 

 from the other.. But, apart altogether 

 Irom their nutritive value, this practice 

 is not to be recommended, since the spores 

 would pass through the alimentarv canal 

 of the animal uninjured, and in this wav 

 become widelv distributed. 



Germination of Spores. 



The spores are at lirst in, clusters, but 

 these soon l)reak up (Fit^^ 5). 'J'hey are 

 shown much magnified in Fig. 6 where 

 thev are seen to be generally globose with 

 line warts all over their surface. The 

 maize from which the spores were ob- 

 tained for germination Avas taken from 

 the crop about the midtUe of iNbuch, and 

 the smutted cobs were still contained 

 within their enveloping leaves. The smut 

 spores were placed in tap water on a 

 microscopic slip and jjlaced under a bell- 

 jar and in 17 hours several had formed 

 germ tubes (Figs. 7 and 8) with two to 

 four partitions across. In 21 hours the 

 minute reproductive bodies or conidia 

 were formed, both at the end and sides 

 of the tube, but the co-nidia at the end 

 were always formed first (Fig. 9). 

 Occasionallv the germ-tube may branch 

 as in Fig. 10. Sometimes a .single spore 

 mav produce three germ-tubes as in 

 fig. II, and thus the number of conidia 

 are immensely multiplied. The conidia 

 thus formed bud in a veast-like manner 

 (Fig. 9) and chains arise bv sprouting, 

 J. MAIZE coii I'AHiiAi.LV SO that a single spore may give rise 



SMUTTED. to innumerable conidia and secondary 



(two-thirds natural size.) conidia. 



