Part 69

Second, the arteria circumflex femoris, which passes between the sartorius and vastus internus and extends dorsalward, supplies the sartorius muscle, the vasti muscles, and the ilio-trochanteric region.

Third, the femoral artery, which passes beside the vena cruralis and extends down the posterior surface of the thigh to the knee-joint, supplies the upper thigh muscles with the exception of the adductor muscles.

FIG. 66.—Blood-vessels and nerves of the posterior extremity. Outside view. 1, Anterior tibial artery. 2, Metatarsal artery. 3, Digital arteries. 4, Vena cutaneous crurus. 5, Ischiadic artery. 6, Vena cruralis. 7, Lateral cutaneous branch of the ischiadic nerve. ]

FIG. 67.—Blood-vessels and nerves of the fore limb. Outside view. 1, Median nerve. 3, Ulnar nerve. 4, Radial artery. 5, Recurrent ulnaris artery. 6, Twigs of ulnar artery to wing feathers. ]

The =ischiadic artery= (Fig. 69, No. 9) forms the main artery of the posterior extremity. This artery, the largest vessel of that region, is given off from the posterior aorta and passes ventrally over and between two of the main lobes of the kidney. The continuation of the posterior aorta is called the sacralis media (Fig. 64, No. 32). The ischiadic artery gives off a recurrent renalis on the posterior lobe of the kidney (Fig. 64, No. 33). On the left side it gives off a branch to the oviduct and to the ligament of the oviduct. The main trunk leaves the cavity with the ischiadic nerve (Fig. 65, No. 1) through a foramen formed by the os ilium and the os ischium. It sends branches into the adductor muscles of the upper and the lower thigh. It gives off anastomotic branches which unite with those from the femoral artery. At the flexure of the knee-joint it gives off two branches to that region (Fig. 69, No. 10). It gives off another branch to the gastrocnemius muscle and one to the flexor perforans digitorum. It terminates in the anterior and posterior tibial arteries.

FIG. 68.—Blood-vessels and nerves of the fore limb. Inside view. 1, Vena humeri profunda. 2, Brachialis longus inferior. 3, Brachialis profunda. 4, Radial artery. 6, Ulnar artery. 7, Ulnar arterial branch to thumb. 8, Digital branch of ulnar artery. 9, Ulnar artery. ]

The first, the tibialis postica (Fig. 69, No. 12) passes between the gastrocnemius and the deep flexors giving off branches in its course to the skin and to other parts, and disappears shortly below the intertarsal joint.

The second, the tibialis antica (Fig. 66, No. 1; Fig. 69, No. 11), is often the larger of the two arteries. The anterior tibial artery gives off branches to the knee-joint and to adjacent structures. It gives a large branch to the head of the gastrocnemius muscle. It passes to the posterior surface of the tibial head and gives off the peroneal artery, which passes through the membrana interossea located between the tibia and fibula giving branches to the anterior side of the membrane of the patellar region of the knee-joint. It gives branches to the anterior side of the lower thigh and finally terminates subcutaneously in the anterior tibial plexus.

The main portion of the anterior tibial artery passes downward along the posterior surface of the membrane located between the tibia and fibula, and sends branches for the flexor digitorum communis et profundus. It then breaks through the membrane, reaches the anterior side and there communicates with the anterior tibial plexus. It gives off branches to the muscles on the anterior side of the lower thigh and the skin, and passes between the outer and the middle malleolus of the tarsal bones. It passes to the plantar surface and divides between the toes. In addition to the plantar branches there are given off dorsal branches between the third and the fourth toes. These branches form the direct continuation of the dorsal vessels of the anterior tibial plexus.

FIG. 69.—Blood-vessels and nerves of the femoro-tibial region. A section of the tibia removed.

A. Veins, arteries and nerves dissected as in B.

B. V, Vein. A, Artery. N, Nerve. 1, Vena poplitealis. 2, The three veins forming the vena poplitealis. 3, Vena femoris interna profunda. 4, Vena femoris anterior. 5, Vena cruralis. 6, Vena cutanea abdominalis femoralis. 7, Vena cutaneous cruralis. 8, Deep vein of the knee-joint. 9, Ischiadic artery. 10, Branches of ischiadic artery to flexure of knee. 11, Anterior tibial artery. 12, Posterior tibial artery. 13, Ischiadic nerve. 14, Trunk (a branch of the ischiadic) which gives off the superficialis peroneus and peroneus profundus. 15, Median branch of ischiadic nerve. 16, Superficialis peroneus. 17, Lateral branch of the ischiadic nerve. ]

The =arteria pudenda communis= (Fig. 70, No. 20) passes to the depressor coccygeus muscle, gives off a branch to the caudal part of the kidney, crosses the ureter, provides the ischio-pubic and pubio-coccygeus, or depressor coccygis lateralis, muscles, and on the lateral rim of the latter muscle it gives off the arteria hemorrhoidalis intima. This artery passes to the bursa of Fabricius and to the end of the cloaca. It enters into the ischio-coccygeus muscle, and divides into the arteria pudenda externa, and in ducks, the arteria profunda penis. These branches supply the vas deferens, the ureter, the cloaca, the penile structure, and the muscles of these parts.

FIG. 70.—Blood-vessels of a Cornish cock. 1, The left pulmonary artery. 2, Right pulmonary artery. 3, Left brachio-cephalic artery. 4, Left subclavian artery. 5, Left carotid artery. 6, Right brachio-cephalic artery. 7, Posterior aorta. 8, Posterior vena cava. 9, Left pulmonary vein. 10, Right pulmonary vein. 11, Celiac axis. 12, Anterior mesenteric artery. 13, Ischiadic artery. 14, Crop. 15, Superior artery of the crop and vein of same name. 16, Testicular or ovarian artery. 17, External iliac artery. 18, Intercostal nerve. 19, Median sacral artery. 20, Arteria pudenda communis. 21, Anus. 22, Vena hypogastrica. 23, Right vena hepatica magna. 24, Left vena hepatica magna. 25, Vena iliaca interna. 26, Vena iliaca communis. 27, Vena iliaca externa. 28, Vena coccygo-mesenterica. 29, Vena umbilicalis. 30, Vena suprarenalis. 31, Origin of the pars renalis. 32, Lumbar veins. 33, Vena epigastrica. 34, Lumbales (arteries). 35, Anterior division of the lumbo-sacral plexus. 36, Posterior division of the lumbo-sacral plexus. 37, Left anterior vena cava. 38, Right anterior vena cava. ]

=The Sacralis Media.=—The median coccygeal artery (Fig. 70, No. 19) forms the single extension of the sacralis media. It gives off lateral branches between the caudal vertebræ which supply the dorsal muscles of that region and the skin. The third pair are the largest. These are the arteriæ coccygeæ laterales, and are located on the dorsal side of the tail, they supply the tail glands and rudder feathers, the main tail feathers, or rectrices. A small arterial twig is given off to the papilla of each rectrix.

THE VENOUS TRUNKS

The venous blood enters the lungs from the right ventricle through the two pulmonary arteries (Fig. 70, No. 1 and 2).

The two pulmonary veins (Fig. 70, No. 9 and 10) collect the arterial blood from the lungs, and empty it into the left auricle.

There are three venæ cavæ which collect the systemic blood and empty it into the right auricle. These venæ cavæ are two anterior (Fig. 70, No. 37 and 38) and one posterior (Fig. 70, No. 8).

Each anterior vena cava is formed by the union of a vena jugularis, a vena vertebralis, and a vena subclavicularis (Fig. 63, No. 15).

FIG. 71.—Veins of the liver of a fowl. 1, Vena mesenterica communis. 2, Vena portalis propria. 3, Anterior vena mesentericus. 4, Vena portalis dexter. 5, Vena portalis sinister. 6, Posterior vena cava. 7, Celiac axis. 8, Base of the heart. 9, The liver. 10, Hepatic veins. ]

The jugular vein is formed by the union of the vena cephalica anterior, and the vena cephalica posterior.

The jugular vein (Fig. 62, No. B, 3) passes along the side of the neck and lies near the trachea, the esophagus, and the pneumogastric nerve. Near the base of the skull the two jugular veins, the right and the left, are connected by a transverse vein. By this anastomosis part of the blood from the left jugular vein is sent into the right. Therefore the right jugular vein is larger than the left. The jugular veins collect the blood from the tongue region, the thyroid, the esophagus, the trachea, the crop, and other structures along its course through the cervical region.

The =vertebral veins= are divided into the anterior and the posterior, or the inferior and the superior. The anterior vertebral vein is located in the cervical region and collects the blood from the brain and the inner part of the head. The vertebral vein passes along the dorsal side of the spinal cord.

BRANCHES OF THE VENÆ CAVÆ ANTERIORES

( Venæ linguales ( Vena occipitalis lateralis ( Vena occipito-collores ( Vena ascendenes lateralis ( Venæ colli cutineæ ( Venæ esophagealeæ ( Venæ tracheales ( Vena ( Vena subscapularis ( jugularis ( Venæ glandularum thyroidearum ( ( ( Vena occipitalis ( Sinus foraminis ( ( ( interna ( occipitalis ( ( Vena ( ( ( vertebralis ( Vena vertebralis posterior ( Vena intercostales Vena cava ( ( ( Vena vertebralis anterior anterior ( ( Vena vertebralis ( Vena vertebralis lateralis dorsalis ( Venæ intercostales ( ( Venæ coronariæ ( Vena subclavicularis ( Vena thoracica interna ( Vena intercostales

( Vena pharyngea superior ( Vena muscularis depressoris mandibularis Vena facialis ( Vena muscularis colli anterior superioris communis ( Vena lingualis ( Vena sublingualis et sphenoidea

The posterior vertebral vein is located in the dorsal region, passes backward and receives the blood from the dorsal neck region and from the intercostal veins and from the vertebral segments and adjacent regions.