DISEASES OF THE OX AND SHEEP. 269. 



showing it to be due to a particular fungus termed actinomyces 

 (a/ctis, a ray ; muces, a fungus), or the ray fungus. Often have 

 we spoken in these pages of the germs of disease, and not yet 

 can we dismiss them from careful consideration, of such trans- 

 cendent importance are they. Let us very briefly review the 

 varieties of vegetable germs, or fungi, which cause so much 

 misery to man, animals, both high and low, and to plants both 

 great and small. Their influence is stupendous in all seasons, 

 and in all climes. 



Firstly, there are the Schizomycetes, members of which group 

 cause anthrax, tubercle, foot-and-mouth disease, cattle-plague, 

 cholera, swine-fever, scarlet-fever, diphtheria, influenza, measles, 

 small-pox, typhoid-fever, rabies or hydrophobia, locked-jaw, 

 and other diseases. However, the actual causation of some of 

 these diseases has not, as yet, been absolutely demonstrated. 

 This group, of course, includes also vast numbers of mem- 

 bers which do not act as causes of disease. Secondly, there 

 are the Yeasts or Blastomycetes, one member of which causes, 

 the disease termed Thrush. Thirdly and lastly, there are the 

 Moulds or Hyphomycetes. These, like the second group, have 

 but little power of invading living tissues. Members of the 

 Moulds cause the various varieties of Ringworm, the Muscardine 

 disease of silkworms, the Madura foot of India. Our readers 

 are probably familiar with the common green mould, Penicillium 

 Glaucum, which grows on jam, bread, damp leather, old boots, 

 &c. The fungus itself is found under the microscope to con- 

 sist of masses of branched filaments springing from a single celU 

 To the Moulds belongs the fungus Puccinia Graminis, which 

 causes the mildew of wheat. *' Smut " which attacks the 

 flower of wheat is caused by the Uredo Segetum, likewise a 

 mould. *'Bunt," or the disease which invades the seed itself, 

 is caused by another fungus, the Uredo Fcetida. 



Ergot, which attacks rye and other grain, as well as rye-grass 

 and other grasses, is composed of the compact filaments or 

 mycelium, as it is generally termed, of another fungus. When 

 invading pasture grasses, ergot is said to be the cause of some 

 outbreaks of abortion in cows and ewes, and to cause that disease 

 in horses known as " grass staggers," or " enzootic paraplegia." 

 The fungus which causes the potato disease is the Botrytis 

 Infestus. We might enumerate many others, but we shall 



