HISTOLOGY AND CHEMISTKY OF FUNGI 55 



being a nutritive material also acts as a stimulant. The position of 

 sulphur, as an important nutritive element, is doubtful. It is inferred 

 that because this element forms an important constituent of the albu- 

 minoids, that it is, therefore, essential to fungi, but there are no re- 

 liable experiments which prove that to be so. Awaiting more detailed 

 investigations, sulphur has been included in the above list of nutri- 

 tive elements. The source of the C, H, and O which form such an 

 important part of the food of fungi is the dead or Hving bodies of other 

 plants and animals, principally plants in which are found sugars, 

 starch, cellulose, mannite, citric acid, and other bodies of organic origin. 

 The source of nitrogen is similarly from soluble nitrogenous bodies, 

 peptones, propylamin, asparagin and others, but few if any of the 

 higher fungi can utihze free atmospheric nitrogen, as can the bacteria 

 which form the nodules on the roots of leguminous plants, described in 

 a former section of this book. The various culture media on which 

 bacteriologists and mycologists cultivate successfully a large series of 

 bacteria and fungi will be considered in a subsequent chapter. Modern 

 research along the lines of technique has demonstrated many im- 

 portant points about the growth and nutrition of the higher fungi 

 and these will be discussed, as we proceed to the end of the book. 



The chemic investigation of the fungi began with the refinements 

 in the technique of modern organic chemistry and much has been pub- 

 lished on the subject, so that there is a bibliography too voluminous to 

 give. Much of the most important chemic work on fungi published 

 prior to 1890 will be found in Zopf's "Handbook." No general work 

 of this kind has recently appeared, so that we must depend on recent 

 original papers on the chemistry of fungi, and in part on the statements 

 of Zopf's great book. The following inorganic elements have been 

 found in fungi: chlorine, sulphur, phosphorus, sihcon, potassium, 

 sodium, lithium, calcium, magnesium, aluminium, manganese and 

 iron. Manganese has been found in the cap of Lactarius piperatus. 

 Aluminium has been reported as occurring in the ash of lichens. The 

 mean of a number of analyses^ of mushroom {Agaricus campestris), 

 truffle (Tuber), Morchella esculenta, two other species of MorcheUa, 

 species of Boletus, a,nd Polyporus officinalis is as follows: potassium 45 

 per cent., phosphoric acid 40 per cent., magnesia 2 per cent., sodium 

 1.4 per cent., calcium 1.5 per cent., iron oxide i per cent., silicic acid 



'ZoPF, Wilhelm: Die Pilze: ii8. 



