INTRODUCTION. 9 
attached, very gentle pressure should then be exerted on the 
plunger, until the blue solution appears in the lacteals. To 
inject all the lacteals it is necessary to insert the cannula into 
the wall of the intestine at a dozen different places. To fill 
the thoracic duct, injection may be made into the large 
lymphatic gland lying at the point where the converging 
hlood-vessels of the mesentery meet. The best solution for 
injecting the thoracic duct is made by dissolving 7 gm. of 
gelatin in a warm Berlin blue solution (4 gm. of Berlin 
blue to too c.c. water). This should be filtered through a 
single layer of absorbent cotton and then injected while still 
quite warm. In all cases injections to fill the lymphatics 
must be warm and must be pushed in very slowly. These 
lymphatic injections are best preserved by injecting the 
trachea and intestine with 95% alcohol and immersing the 
cat in a jar of 70% alcohol. 
Preparation of a Mammal for Dissection of the 
Muscles, Peripheral Nerves and Viscera.—The simplest 
method is to anesthetize the animal as before described and 
then remove the skin, taking great care to avoid cutting 
away the superficial muscles. The cannula should be 
pushed through into the trachea and 100 c.c. of 15% for- 
maline injected to fill the lungs. An equal amount of 
formaline should be injected into the stomach through a 
glass tube pushed down the esophagus. The same quantity 
of formalin should be injected at two or three different 
places into the intestines by making a median incision into 
the abdominal wall and pulling out a loop of the intestine 
into which the cannula may be thrust. The specimen is 
then to be immersed in a jar of 5% formalin. <A better 
method is to inject into the carotid artery 200 c.c. of glyceri- 
nated formalin (water 140 c.c., glycerin 30 c.c., formalin 
30 c.c.), and half that amount into the intestine and trachea. 
The specimen may then be preserved in 5% formalin. 
