ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
677 
cells of the cornea prepared with gold chloride. Similar cells were 
found in other parts of the frog, when the tissues were examined after 
the same method. Analogous cells were observed in the mesentery of 
the crested Triton, and when examined in their own plasma were found 
to be devoid of movement and incapable of amoeboid prolongation. 
If a non-microbic peritonitis be induced, as by the injection of a dilute 
solution of silver nitrate into the sac, the clasmatocytes become changed, 
in situ, into lymphatic cells, they reassume their embryonic form, and 
multiply rapidly by direct division. Hence they are the principal source 
of suppuration. The clasmatocytes are neither fixed connective tissue- 
corpuscles, nor are they leucocytes. 
Toxic Principle of Bacillus lactis aerogenes.* — Prof. J. Denys 
and M. E. Brion record experiments made with B . lactis aerogenes ( B . 
pyogenes d’Albarran and Halle), an organism first found almost in a state 
of purity in the stools of suckling infants by Escherich. Recently, A. 
Morelle has shown that this organism plays an important part in urinary 
affections, and though much of importance as to its morphology and 
biology are known, its toxic principles have been little studied. Tho 
organism was grown on potato, whereon it forms a thickish layer, which 
is easily scraped off and can be weighed and mixed with fluids. As a 
cultivation medium potato has the further advantage of being free from 
pepton, sugar, and other substances entering into the composition of 
bouillon and gelatin. The pale yellow-brown growth was weighed and 
mixed up to 10 per cent, with distilled water or physiological solution, 
and then ether or chloroform added to kill the microbe. 
The effect of large doses on the rabbit was an energetic action on 
the central nervous system. After an extremely short stage of excite- 
ment, general paralysis set in, and this might be accompanied by tetanus. 
In smaller doses the most striking phenomenon was emaciation. The 
poison was obtained by passing the aqueous emulsion through a 
Chamberland or Nordtmeyer filter, and using the filtrate or simply the 
clear supernatant fluid; and in course of these observations it was 
determined that the poison was extremely diffusible in water, and that 
2-3 cubic centimetres of the fluid obtained either by filtration or deposit 
are about equivalent to one cubic centimetre of the emulsion. The 
poison showed a remarkable resistance to high temperatures, there being 
no apparent diminution of its virulence after exposure to 100° for 15-20 
minutes. After 45 minutes to 3 hours at the same temperature, there is 
manifest diminution, and after an exposure of 6 hours the dose requires 
to be four times as large. 
The nature of the poison was examined by Brieger’s method, but no 
ptomaines from potato cultivations were obtained. Gautier’s method and 
attempts to extract an alkaloid by solvents such as chloroform, ether, 
and alcohol, either simply or after acidification with acetic or hydro- 
chloric acid, were equally unsuccessful. The poison hitherto suspected 
of being a toxin was afterwards determined to be a toxalbumin. It is 
soluble in water ; it is precipitated from this solution by alcohol ; it 
is of a colloid nature and non-dialysable ; it becomes incorporated with 
precipitates such as calcic phosphate. 
The authors further find that neither the gastric nor the pancreatic 
* La Cellule, viii. (1892) pp. 305-32. 
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