538 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
reaction is induced, only a blue colour. When, however, lactic fermen- 
tation is set up in milk or when it is artificially promoted by the simul- 
taneous addition of sodium lactate and glucose, the blue pigment is 
produced. In bouillon the addition of grape-sugar suffices, since here 
the sarco-lactic acid of muscle-juice is present. 
Microbes of the Mouth and their Relation to Leptothrix 
buccalis.* — Sig. F. Yicentini makes an elaborate attempt to show 
that all or almost all the bacterial forms found in the expectoration are 
offshoots or organs of a single vegetable organism ( Leptothrix buccalis ), 
and that the different shapes which are assumed are in great measure 
due to the constitution of the nutrient medium. 
According to the author’s view the term micro-organism would 
apply to the microphyte as a whole, and bacterium, bacillus, &c., would 
represent particles, collections of particles, and stages in the existence 
of the microphyte, which have not only a separate existence but the 
faculty of endless repetition. It is also stated that Leptothrix possesses 
a much higher degree of organization than is usually supposed, having 
true reproductive organs and an elaborate method of fructification. The 
former method of multiplication and development is easily observable 
with comparatively low powers, but the latter requires special procedures 
and adequate optical apparatus. 
The author’s view of the special function of the buccal and nasal 
microbes seems to be that they have been placed there by nature firstly as 
an aid to digestion, and secondly as a defence against the micro-organisms 
of the external world. An identical vegetation garrisons the genito- 
urinary tract ; hence it would seem that the human species is defended by 
a single microphyte which changes its form and habits according to the 
soil and climate in which it happens to be residing. 
Human Saliva and Pathogenic Micro-organisms of the Mouth.f — 
Dr. G. Sanarelli concludes from a series of experiments that human 
saliva is a very unfavourable cultivation medium for certain pathogenic 
microbes, since it possesses the power of destroying them more or less 
quickly unless their number be too great ; and that although it permits 
the development of certain species ( Pneumococcus ), it alters their type 
and renders them weak or even inert. 
The saliva was obtained from various healthy individuals, and was 
then passed through a Chamberland’s filter into test-tubes, each having 
10-15 ccm. The fluid in these tubes was then inoculated from cultiva- 
tions of the following micro-organisms : — St. pyogenes aureus , St. pyogenes, 
Bad. Diphtherise , M. tetragenus , Pneumococcus, B. typhosus, cholera 
spirillum. 
Presence of Bacillus typhosus in Bordeaux Water 4 — M. G.Martin 
states that at the end of 1887, and at the beginning of 1888, Bordeaux 
was visited by an epidemic of typhoid fever from which 154 cases died, 
and in 1890 by one lasting four months, 71 cases dying. 
* Atti R. Accad. Med.-Cki. di Napoli, xliv.’ 76 pp. (1 pi.) (separate copy). 
f Centralbl. f. Bakteriol. u. Parasitrnk., x. (1892) pp. 817-22. 
X Rev. Sanit. de la Province, 1891, p. 93. See Centralbl. f. Bakteriol. u. 
Purasitenk., xi. (1892) p. 413. 
