Studies on ruminant saliva. 1. The composition and output of sheep's saliva

SULPHATES 99 taining magnesium and ferrous sulphates as the sole source of sulphur.2. This has demonstrated the universal import- ance of inorganic sulphates in the metabolism of moulds, since all species or strains tested utilized 10 % or more, 56 utilized 60 % or more, and 16 over 90 % of the inorganic sulphate in the medium.3. A more detailed examination of the sulphur metabolism of seven species of Penicillium, six strains of A8pergillu8 terreu.sThom, and one strain of A. fumigatus Fresenius, 'grown on the same medium, revealed the fact that some of them form considerable amounts of 'ethereal sulphates' while others, particularly Penicillium notatum Westling, give large yields of other, probably organic, sulphur compounds, of at present unknown nature.