IIO 
MAMMALIAN ANATOMY 
and fibrous connective tissue. Draw , showing characteristic 
differences. 
Examine sections through various organs for identification of 
veins and arteries which appear in such sections. 
D. LOCATION OF SUPERFICIAL BLOOD VESSELS IN THE 
LIVING HUMAN SUBJECT. (Cf. manikin and atlases or 
text-books for identification of vessels.) 
Arteries (distinguished from veins by the presence of a pulse). 
Carotid, facial, temporal, axillary, radial, femoral. 
Veins. —Jugular, axillary, femoral, popliteal, and in many 
regions of the body, particularly in the distal portions of the 
extremities, conspicuous meshworks of subcutaneous veins. 
Choose some region as, for example, the back of the hand or the 
flexor surface of the wrist, and carefully study this meshwork as 
to (i) symmetry of the two sides of the same individual, (2) 
amount of variation exhibited by different individuals, (3) the 
location of valves, readily demonstrated by exerting sufficient 
pressure between the region under observation and the heart to 
prevent the onward flow of blood, which thus distends the vein 
between the point where the pressure is exerted and the nearest 
valve, since the blood accumulates proximal to the latter and is 
prevented by it from flowing backward. Record by notes or by 
drawing. 
E. DEMONSTRATIONS OF THE MOVEMENT OF THE 
BLOOD. 
1. Demonstration of the circulation of blood in a three-day 
chick: Break the egg into a dish of warm physiological salt solu¬ 
tion, being careful not to rupture the yolk. With the naked eye 
and under the dissecting microscope note the general plan of 
circulation (cf. chart) and the pulsation of the heart. 
2. Demonstration of the movement of the blood 1 in the web 
1 In case a frog is used for this demonstration it should first be pithed and the 
part to be examined then pinned out, but not too tightly stretched, over an aperture 
in a sheet of cork and placed upon the microscope stage. Keep the parts moist with 
physiological salt. If a salamander be used, it may be anesthetized by placing it in 
a solution of chloretone and then examined under water in a watch glass or stentor 
dish under a binocular dissecting microscope or a low power of the compound 
microscope. 
