1885.] Scientific News. Q21 
by the use of two injecting fluids, òf different densities, one pass- 
ing through the capillaries, the other arrested at the capillaries, 
the whole vascular system may be injected from the aortic arch. 
The application of the principle is as follows: (1) The animal 
is immersed in tepid. water an 
the heart is uncovered. (2) The 
apex of the single ventricle, in the 
case of an amphibian, or of the 
left ventricle in the case of higher 
animals is then laid widely open 
and the blood allowed to flow 
freely from the auriculo-ventri- 
cular aperture (see # in the 
figure). (3) A cannula is then 
inserted a short distance into the 
arterial bulb and the first ligature 
is fastened around the nozzle. 
kuaa icle, thus surrounding the Fic, 1.—Illustrating method of prepar- 
auriculo-ventricular apertures, (4) ing the frog’s heart. V, ventricle; ZA, 
An ordinary gelatine injecting left auricle; ø, auriculo-ventricular open- 
mass, stained deep red or purple, 783 1¢ £ and se Z, first and second 
mee ‘ igatures; C, cannula. 
is in the meantime prepared. 
When the body is thoroughly warmed, this mass is slowly in- 
jected. As the second ligature is still loose, a quantity of blood 
gradually followed by the gelatine issues from the auriculo-ven- 
tricular opening. (5) When the gelatine begins to run pretty 
clear, the second ligature is fastened and the syringe containing 
gelatine is replaced by another containing a red plaster-of-paris 
injecting mass. The latter drives the gelatine contained in the 
arteries before it as far as the capillaries, thus completely filling 
the venous system. When the gelatine is thoroughly cooled 
the animal is ready for dissection. - 
This method can be applied with considerable ease to all the 
smaller animals, such as frogs, lizards and pigeons, in preparation 
r class-work or investigation. Its advantages are numerous. 
Among its disadvantages may be mentioned the fact that alcohol 
cannot well be used as a preservative, because it dehydrates the 
gelatine, causing it to shrink and break up the veins. This diffi- 
culty is entirely obviated, however, by the use of Wicker- 
Sheimer’s fluid, in which the injection remains perfect for an in- 
definite time —Henry F. Osborn. 
:0:—— 
SCIENTIFIC NEWS. 
—The Washburn Biological Survey of Kansas, says the 
Kansas City Review, has for its object “to investigate the fauna 
