210 ABSTRACTS OF CHEMICAL PAPERS BACTERIOLOGICAL, PHYSIOLOGICAL, ETC. Effect of Pasteurisation on Mould Spores. C. Thorn and S. H. Ayers. (J. Agric. Research, 1916, 6, 153-166.)-Studies were made with spores from pure cultures of a series of moulds, including over forty species of Penicillium, a large number of Aspergillus and of the mucors, and, in some experiments, Oidium lactisBACTERIOLOGICAL, PHYSIOLOGICAL, ETC.211 ill ois t ur e ... ... ... ... Dry substance ... ... ... ... Ash ... ... ... ... ,, in dry substance ... ... ... ,, in ash ... .. ..^ ... Potash iK,O) ... ... ... ... and one species of F,usarium. I t was found that the c L bulk " process of Pasteurisa- tion in which milk was heated to 62.8" C., and maintained at that temperature for thirty minutes, killed the conidia of every species investigated, except those of Aspergillus repens, A.Jclavus, and A. fumigatus. The moulds which survive are found only occasionally in milk. The '' flash " process of Pasteurisation in which milk was heated to 7 3 0 9 ~ C. for a period of thirty seconds destroyed the spores of all the moulds tested, with the exception of many spores of one form and occasional spores of three more forms.At 79.5" C. only occasional spores of two forms developed. When the heating process was performed in dry air for a period of thirty seconds at 93.3' C., 31 out of 42 forms of Penicillium and 7 out of 24 forms of Aspergillus were destroyed, but none of the cultures of nzucors. A temperature of 121.1" C. over a period of thirty minutes killed all the forms of Penicillium spores tried, but left an occasional living spore in one species of Aspergillus and 3 out of 6 rnucors.Careful study of the cultures showed that the first effect of heating was to delay germina- tion. I t was found that there was frequently a, survival of a few spores where a majority of the spores die; there may be therefore a difference of as much as 11" C.between the temperature at which an occasional culture is completely killed, and that at which cultures of that species are uniformly killed. These results resemble those obtained in determining the thermal death-point of bacteria. The results obtained were studied in an attempt to correlate heat resistance with size of spore or thickness of spore wall, but no such correlation was found. H. I?. E. H. Per Cent. Per Cent. 91.60 88.20 8.40 11*80 2.40 1-77 1.14 1.05 13.73 9.03 45.90 57.16 i Potash in Banana Stalks and Skins. R. H. Ellis. (J. XOC. Chem. I d . , 1916, 35, 456-457 ; 521.)-Analyses of banana stalks and skins yielded the following results : Stalks. I Skins.