The Beneficial and Injurious Influences of Fungi. 195 



shape like to Corne, but in stead of graine it doth yeeld a 

 blacke pouder or dust, which causeth bread to looke blacke, 

 and to have an evill tast : and that Corne where it is, is 

 called smootie Corne and the thing it self, Burnt Corne, or 

 Blasted Corne. 



Three woodcuts are given, perhaps the oldest pictures 

 known of the effects of the pest Ustilago. These woodcuts, 

 illustrating Gerard's Herbal, were printed from blocks procured 

 from Frankfort, being the same blocks which had been used for 

 the ' Kreuterbuch,' the German Herbal of Tabernaemontanus 

 in 1588. 



Ergot of Rye (Claviceps purpurea) produces terrible effects 

 when taken into the alimentary canal by man or animals, 

 causing gangrene of the extremeties and other maladies. 

 It has the effect of causing muscular contraction and by stopping 

 the supply of fresh blood to the limbs causes them to rot and 

 fall off. It is also extremely injurious to sheep and cattle during 

 the breeding season. Ergot may be observed in almost every 

 rye field during June and July by the blackish horn-like growths 

 taking the place of the grain and projecting from the ears often 

 an inch or more in length. Many of these sclerotia( = compacted 

 mycelium) fall to the ground and remain dormant until the 

 spring, when they produce small drumstick-like bodies covered 

 with flask-shaped cavities filled with spores which, when 

 liberated, infect the flowers of the corn. Many of the grasses 

 and sedges are affected with ergot in a similar manner to the 

 corn crops and are able to convey the infection to the cereals, 

 although it is noticed that the ergots on grasses vary their 

 time of germination to suit the flowering period of their hosts. 



That the ergot of grasses infect corn was suggested last 

 summer by the appearance of a rye field on the edge of a 

 common in the Selby district which was affected to quite ten 

 per cent, whilst near by the wild grasses Lolium perenne and 

 Holcus lanatus were similarly affected, but in the part of the 

 field distant from the grasses the infection of the crop did 

 not reach one per cent. In this country, where the practice 

 of crop rotation is generally followed, the diseases of the crops 

 are not so virulent as where constant growth of the same crop 

 prevails, the interval being usually sufficient for the decay 

 of the resting spores although the vitality of some species is 

 remarkable, for instance, Ergot. In the spring of 1916, some 

 sclerotia of this, labelled July, 1880, was taken from the 

 cabinet and placed on moist sand in a Petrie dish, and in about 

 a month several ascophores of Claviceps purpurea were developed 

 so that the thirty-six years of complete dessication had not 

 destroyed the vitality of the plant. 



Crop rotation has been able to ward off the Black Wart 

 disease of Potatoes (Synchytrium solani), a pest which has 



1917 June 1. 



