No. 462] THE SKATE FOR ANATOMICAL STUDY. 375 
ordinary temperature (20° C.) without warming the animal above 
the temperature of the room. The melted gelatin was slightly 
superheated, and the heavy brass syringe, with rubber tube and 
cannula, was heated by immersing in hot water to a temperature 
about as high as consistent with comfort in handling. By these 
means, the starch-gelatin was introduced into the blood-vessels 
at a temperature considerably above its solidifying point. The 
warm fluid penetrates into the smaller and remote vessels before 
becoming cooled sufficiently to harden, giving quite as full an 
injection of the finer vessels as the cold starch mass ever does. 
The skates which I have injected with starch-gelatin were 
immersed, immediately after injection, in three or four percent 
formalin, which, having been freshly prepared with tap water, 
was considerably cooler than the room temperature. The 
starch-gelatin promptly solidified into a firm mass having the 
consistency characteristic of stiff gelatin. 
The starch-gelatin method described above gives results 
entirely satisfactory for purposes of gross dissection. The 
method may be used under any conditions where the unboiled 
starch mass might be used, but where a mass of the consistency 
of gelatin is to be preferred. The advantage of the starch-gela- 
tin as compared with the raw starch lies in the fact that the 
mixture “sets” and, therefore, will not escape, however much 
the vessels may be cut. The advantage, for the purposes men- 
tioned, of the mixture as compared with pure gelatin is in the 
fact that the starch causes the mass to stop at capillaries, thus 
preventing danger of the injection passing from one set of ves- 
sels into another. Finally, the method is not a particularly 
troublesome one, since the warming of the animal itself — 
usually the greatest inconvenience attending the use of any 
warm injection mass — may be omitted. The superiority of the 
starch-gelatin is most marked in the injecting of a blood-system 
containing large thin-walled sinuses, a$ in the case of the venous 
system of the skate. Its advantages over plaster of Paris for 
this purpose, are obvious and it is scarcely more troublesome to 
use. : 
The injection of the arteries of the skate is a comparatively 
simple matter. The afferent branchial vessels may be injected 
Bu 
