160 G. F, DOWDESWELL. 
shortly all disappear; and still further, by the fact stated by 
Cohn (loc. cit.), that they are dissolved by potash, which is con- 
trary to the properties of all known Bacteria, the resistance of 
which to alkalis and acids is regarded as their chief and most 
reliable characteristic. That they are portions of the proto- 
plasmic substances of the corpuscle appears to be evident ; as 
such they would possess contractility as long as they retained 
the vital properties of protoplasm, though in such attenuated 
filaments, the movements which they exhibit may be merely phy- 
sical, the result of the currents which are never absent from a 
preparation of blood under the microscope, unless it be sealed, or 
until coagulation occur. 
The next and latest description of these processes is in an ex- 
cellent paper by Gaule,! which describes their appearances in defi- 
brinated frogs’ blood, treated on the warm stage at a temperature 
of 30° to 82°C. with a solution sod. chor. 0:4 to 0°8 per cent.; the 
method here adoped for defibrinating the blood was by shaking 
it up sharply in a mixing glass with salt solution and a little 
mercury, which subsides and carries the fibrin with it; a drop 
of the supernatant fluid is then placed on the warm stage, treated 
with more salt solution, and sealed. The author describes the 
formation of these processes from the large majority of the cor- 
puscles; a staff-shaped body first appears in which some bright 
granules or strie are visible, this elongates, becomes detached, 
pointed at both ends, and commencing a spiral movement, 
wriggles about over the field of view; coming in contact with 
other blood-corpuscles it adheres to them, dragging them after it, 
strongly resembling in appearance minute worms, but, as the 
author observes, in outward appearance only, and not in their real 
nature. In length these bodies equal about half the diameter 
of a red blood-corpuscle, but their character varies with circum- 
stances, the vigour of the frog, the strength of the solution, &c. 
The author concludes that these are processes evolved from the 
constituent protoplasm, the stroma of the corpuscle. I can 
confirm the author’s results in all respects. I have not found it 
necessary to defibrinate the blood to obtain these appearances, 
though to do so, simply whipping it is sufficient; nor is it 
necessary to seal the preparation, though this, by preventing 
evaporation, may somewhat prolong their duration. 
Similar appearances have been described in other protoplasmic 
bodies, not only in the white blood-corpuscles, but in Amcebe 
(Protozoa) too,” under the action of dilute salt solution ; in some 
1 ¢ Archiv f. Anat. u. Physiol.,’ 1880, Th. ] and 2,s.41—57. “ Ueber 
Wiirmchen,” ete., von J. Gaule. 
2 Dr. Vincent Czernay, “ Beobacht. iiber Amceben.,” ‘ Arch. f. Mikros, 
Anat.,’ Bd. v, 1869, s. 158—166. 
