ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
533 
The effect of an inoculation varies considerably with the infection path, 
each tissue having very different power of resistance, the order of 
sensitiveness being anterior chamber of eye, vascular system, connective 
pleura, meninges, peritoneum. (4) Division of the sciatic nerve favours 
the localization of staphylococci circulating in the blood. 
Hereditary Transmission of Characters artificially acquired by 
Bacillus Anthracis.* — M. C. Phisalix finds that by heating successive 
generations of anthrax cultivations up to 42°, these bacilli lose their 
power of forming spores, and that when the fourteenth generation is 
reached the cultivations are not only asporogenous, but injections into 
mice are inert. As a result of these experiments, the author infers that 
slight modifications impressed on these microbes may become permanent 
in the course of a certain number of generations, and that under these 
conditions is produced a real accumulation of hereditary influences. 
Effect of Carbonic Acid on the Vitality of Micro-organisms.j-— 
The results obtained by Herr C Fraenkel from experiments with a view 
to ascertaining the action of carbonic acid on micro-organisms may be 
summed up very shortly. A certain number of bacteria will thrive in 
C0 2 almost just as well as in ordinary atmospheric air. Others may 
grow in C0 2 , but their development is more or less retarded or impeded. 
A third group will not grow when cultivated under the usual conditions, 
but will develop at incubation temperature. A large number, for 
example many saprophytes, will not thrive in C0 2 under any conditions ; 
these may not be killed by the gas, for on replacing it with atmospheric 
air they will begin to grow again. Some bacteria, and among these are 
important pathogenic species, are killed by C0 2 ; yet, notwithstanding 
its inhibitive and partially antiseptic action, C0 2 has no power to arrest 
decomposition ; nor does it appear to possess any power to attenuate the 
virus of pathogenic bacteria. 
A relatively slight addition of ordinary atmospheric air to the C0 2 
will allow even the species most sensitive to the presence of carbonic 
acid to develope. 
In all forty species of micro-organisms were experimented with, and 
these included the best known of the pathogenic saprophytic phos- 
phorescent, &c., bacteria, e. g. Bac. typhi abd , Pneumococcus , bacillus of 
lactic fermentation, yeasts, M. prodigiosus, Bac. Indicus and phosphor escens, 
Proteus vulgaris , St. pyogenes , St. pyogenes aureus , &c. 
Effect of Drying on some Pathogenic Micro-organisms.j: — Sigg. S. 
Sirena and G. Alessi used the following pathogenic bacteria in some 
experiments made for the purpose of ascertaining the effect of drying on 
their vitality, viz. : — cholera, anthrax, swine erysipelas, enteric, fowl 
cholera, glanders, and Fraenkel’s diplococcus. The drying process was 
effected by means of sulphuric acid, chloride of calcium, incubation at 37°, 
dry room in the shade, moist room, in vitro exposed to sunlight, sunlight 
and free air. 
The authors sum up their results as follows: — (1) Drying is a 
* Comptes Rendus, cxiv. (1892) pp. 684-6. 
t Zeitschr. f. Hygiene, v. (1889) pp. 332-62. 
j La Riforma Med., 1892, Nos. 14 and 15. See Centrulbl. f. Bakteriol. u. 
Parasitenk., xi. (1892) pp. 484-5. 
