ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
95 
and of pathological new formations possess the same power of amoeboid 
movement, for example those of the spleen, the lung, and of lymphatic 
glands. 
The epithelioid cells of the infective granulomata have similar 
functions; thus in tubercle these cells not only take in and digest the 
bacilli, but also the smaller cells which enter into the formation of the 
tubercle nodule. 
From a similar point of view the large multinucleated or giant cell 
is regarded. It is a fighting cell in fact. With regard to quarter-evil 
the conclusions are that the inflammatory process resulting from the 
infection is a protective one, the destruction of the micro-organisms 
being carried out entirely by the amoeboid cells present in the in- 
flammatory exudation. 
With regard to diphtheria it is stated that the diphtheritic bacilli 
are present in the most superficial parts of the membrane only, and that 
the only reason why the bacilli do not penetrate into the tissues is that 
they are arrested by the amoeboid cells present in the diphtheritic 
membrane. 
Microbes of the Mouth.* — M. Th. David has recently brought out 
a work in which he deals, in a very thorough manner, with micro- 
organisms infesting the mouth. The book is well got up and excellently 
illustrated. In the general part the form, staining, and cultivation of 
micro-organisms are first discussed, after which those which inhabit the 
mouth, and from there may pass into the organism, exciting local or 
general disturbances. 
In the general portion the first chapter is devoted to the making 
of staining solutions, the preparation of nutrient media, of plates, &c. 
In the second chapter the more important saprophytes are described 
and discussed, while the third is devoted to pathogenic micro-organisms 
met with in sputum, bacillus of sputum septicaemia, Pneumococcus , 
Friedlaender’s bacillus, Streptococcus pyogenes, Staphylococcus pyo- 
genes aureus and albus. Chapter iv. deals with the microbes pro- 
voking diseases of the mouth and teeth, after which follow practical and 
therapeutic measures for the preservation of teeth — indeed we understand 
that this work is intended for the special behoof of those interested in 
dental work ; but this of course does not in any way detract from its 
merits, which are signalized by M. Pasteur in a laudatory preface. 
Action of Anilin Dyes on the Development and Virulence of 
Microbes.j — MM. Braud and Hugounenq have recently examined the 
behaviour of various anilin pigments towards anthrax, Staphylococcus 
pyogenes aureus, and Gonococcus ; and from their experiments they con- 
clude that, of the dyes examined, methylen-blue and safranin in very 
dilute (2 per cent.) solutions do not damage the growth so much as the 
virulence of the micro-organisms referred to, but that in more concen- 
trated solutions, or after more prolonged action of the dilute, the growth 
also suffers. 
* Paris, 1890, 302 pp., 113 figs. See Centralbl. f. Bakteriol. u. Parasitenk., x. 
(1891) p. 609. 
t Lyon Me'd., 1891, No. 14. See Centralbl. f. Bakteriol. u. Parasitenk., x. (1891) 
p. 615. 
