76 ANTHROPOLOGY. 
‘munis; * and *, peronzeus longus; * and *, peronseus brevis; *, extensor 
communis brevis; * and ’, peronzeus tertius; **, annular ligament on the 
back of the foot. 2g. 17’, flexor digitorum brevis; ?, abductor pollicis; 
*, flexor pollicis brevis; *, abductor digiti minimi; °, flexor brevis digiti 
minimi. fg. 18’, flexor pollicis brevis; *, adductor pollicis; *, transver- 
salis plantaris; *, tendon of the peroneus longus. Mg. 19 interosseous 
muscles of the back of the foot. 
ary. 
Til. THE VASCULAR SYSTEM. 
(ANGEIOLOGY.) 
The Vascular System consists of membranous ramifying tubes, which 
conduct either blood or fluids to be added to the blood for the sake of 
restoring to it the materials necessary for its normal functions. The blood, 
from which is derived the material of life and growth, is furnished by the 
food taken into the stomach, which after undergoing certain operations, 
subsequently to be explained, and after being strained through exceedingly 
fine tubes called lacteals, is introduced into the general circulation by the 
thoracic duct. The blood circulates through all parts of the body mainly 
by the impulsion of a central engine, the heart, which continues pulsating 
at regular intervals during the entire life of the animal. Vessels which 
conduct blood from the heart are known as arteries, while those which 
bring it back again are veins. The former are distinguishable from the 
latter by their exhibiting the phenomena of pulse. The arteries pass to all 
‘parts of the body, dividing and subdividing continually as they recede from 
the heart, until finally they end in ramifications so fine as only to be appre- 
ciable by the microscope. These terminal branches are called capillaries. 
The capillaries are continued into the veins, which present an appearance 
much like that of the arteries, viz. a tree excessively ramifying, with the 
trunk resting on the heart, and the branches ending in the capillaries, which 
latter thus constitute the peripherical medium of communication between 
the arteries and the veins. The blood proceeds from the heart through the 
arteries to the capillaries, where it undergoes certain changes; passing into 
the veins from these, it again reaches the heart, thus performing a round 
known as the circulation of the blood. The nutritious particles of the blood 
pass through the thin walls of the capillaries into the various tissues, for the 
sake of supplying the wear and tear of animal life; the dead or effete por- 
tions are taken up in the state of lymph by another set of vessels called 
lymphatics, which discharge their contents into the veins, ultimately to be 
subjected to certain influences which prepare them for again playing their 
part in the general circulation. The chyliferous system is closely allied to 
the lymphatic. This consists of excessively minute canals, which extend 
from the intestines to the thoracic duct, and are called lacteals, on account 
of their white appearance when distended with the milk-like chyle. 
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