164 



VETERINAEY TOXICOLOGY 



tation, loss of colour and aroma, and possibly poison, it 

 being, perhaps, more likely that the moulds themselves act 

 as poisons. The commonest are Botrytis, PenicilliiMn, 

 Aspergillus, and O'idiwm. 



As regards active principles, the only member of this 

 group, concerning which there is at present definite know- 

 ledge, is claviceps, or ergot. The physiological activity, 



Fig. 9. — Eust and Mildew. 



I part of stem of oat-plant attacked by Piiciyinia grwminis ; B, two of the 

 blotches from A enlarged 20 diameters ; C, P. graminis within the stem, 

 but near the surface, bursting th e cuticle at I>, beneath which are seen 

 the teleutospores ; E, E, spores of Uredo linearis, which sometimes sur- 

 round the teleutospores of P. fframinis ; Q, teleutospores germinating 

 and producing sporidia at H. These sporidia, on germinating, give rise 

 to JEcidiwm herbcridis. 



(From Smith's ' Yeterinary Hygiene.') 



giving rise to the well-defined ergotism of man, is attri- 

 butable, according to Barger and Dale, to an alkaloid 

 ' ergotoxine,' isolated in 1907 by'Barger and Carr.* Along 

 with it is the inactive ' ergotoxine,' and the two together 

 do not form much more than 0*1 per cent, of the drug. 

 Ergot does not appear to exercise much action on rumi- 



* Transactions of the Chemical Society, 1907, p. 337. 



