ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 451 



motile. The cells measure from • 7 to 1 • 2 fx, and produce very resistant 

 spherical spores with a diameter of • 6 fx. It decomposes urea readily 

 but not rapidly, converting only 3 p.c. while another organism, Urococcus 

 urese, has disposed of 5 p.c. of urea. 



Parasites on the Seats of " Cabinets d'aisance." * — F.F. Santschi 

 contributes an elaborate report of bacteriological examinations made on 

 the seats of water-closets, latrines, privies, and other forms of cabinets 

 d'aisance. The seats are divided into two classes, the English and the 

 Turkish. The examination appears to have been carried out with great 

 thoroughness, and according to the most approved methods of bacterio- 

 logical research. Thirty-seven species of microbe were detected, many 

 of them being pathogenic bacteria, but among the latter it is satisfactory 

 to note that B. tuberculosis was not discovered. 



Behaviour of certain Pathogenic Microbes in Milk, Cream, and 

 Cheese, f — Dr. E. Klein, after an investigation of the behaviour of 

 Bacillus tuberculosis, B. diphtheriw, B. typhosus, and Streptococcus, when 

 cultivated in sterilised milk, cream, and cheese, reports that milk incu- 

 bated at 37° forms a suitable medium for the propagation of the tubercle 

 bacillus. When fresh tuberculous deposits were used, milk cultures 

 were rendered highly virulent. Milk was found to rejuvenate cultures, 

 e.g. glycerin-agar, which from lapse of time had lost their power to 

 produce tuberculosis on inoculation. The regained virulence was, how- 

 ever, easily lost again. On sterilised cheese, and in sterilised cream at 

 37°, tubercle bacilli were found to thrive. 



While tbe ability of B. typhosus to thrive in milk is confirmed, cream 

 proved a suitable medium only at about 20° ; for at 37° the microbe 

 disappeared in two weeks. From cheese this bacterium had disappeared 

 within a like period. 



The diphtheria bacillus grew well at 20°, but at 37° was not recovered 

 after a fortnight. Cream and cbeese were unsuitable at both tempera- 

 tures. Streptococcus scarlatinas grew at both temperatures in milk. It 

 could be recovered after two weeks from cream and cheese at 20°, but 

 not at 37°. 



iEtiology of Plague.! — Dr. J- A. Thompson, in a contribution to 

 the aatiology of plague, expresses the opinion, formed from observations 

 made during the epidemic at Sydney, N.S.W., that the communication 

 from rats to man is effected very commonly, and indeed usually, by fleas. 

 The direct evidence adduced, though small, is positive. 



Bacteriological Researches on the Roots and Seeds of Hedysarum 

 coronarium. § — K. H. Nicolai found in the roots of Hedysarum 

 coronarium spherical and rod-like bacteria. As there were no nodules 

 on the roots, it was probable that the bacteria gained entrance through 

 the root-hairs. No trace of albumen was detected in the bacteria by the 

 ordinary tests. The bacteria grew on all the usual media. The addi- 

 tion of asparagin (0*01) and of cane sugar (0*05) to 10 ccm. of gelatin 



* Bull. Boc. Vaudoise Sci. Nat., xxxvii. (1901) pp. 41-90. 

 t Local Gov. Board Rep. 1899-1900 (1901) pp. 577-87. 

 X Journ. Hygiene, i. (1901) pp. 153-67. 



§ Inaug. Diss., Erlangen, 1900, 34 pp. See Centralbl. Bakt., 2" Abt., vii. (1901) 

 p. 301. 



2 h 2 



