674 



BLOOD-VASCULAR SYSTEM OF THE HORSE 



fasciae latse to the fold of the flank, supplying branches to that muscle, the cutaneus, 

 the prefemoral lymph glands, and the skin. 



2. The external spermatic or cremasteric artery (A. spermatica externa) is a 

 very small vessel which arises in a variable maimer. It springs most often from the 

 external iliac near the origin of the latter, but may come from the circumflex iliac, 

 the aorta between the external and internal iliac, or the latter vessel. It accom- 

 panies the cremaster muscle to the inguinal canal, supplies twigs to that muscle, 

 the tunica vaginalis, and other constituents of the spermatic cord (Fig. 575). 



2a. The middle uterine artery (A. uterina media) of the female is regarded as 

 the homologue of the preceding vessel; it has a similar origin, but is a much larger 

 artery. It enters the broad ligament of the uterus, in which it pursues a flexuous 

 course to the posterior part of the horn of the uterus. Its branches are distributed 

 to the uterus and anastomose with those of the other uterine arteries. 



The Femoral Artery (Figs. 575, 576) 



The femoral artery is the main arterial trunk of the thigh. It begins at the 

 level of the anterior border of the pubis, from which it is separated by the femoral 



Fig. 582. — Dissection of Inguinal Region and Medial Suhface of Thigh of Horse. 

 1, External pudic artery; 2, anterior branches of /; 3, posterior branches of 1; ^, transverse anastomosis between 

 external pudic veins; 4-' , venous plexus of dorsum penis; 5, femoral artery; 6, saphenous nerve; 7, anterior border of 

 external inguinal ring; 8, obliquus abdominis internus; 9, posterior border of external inguinal ring; 10, tunica vag- 

 inalis; 11. ductus deferens; i^, cremaster muscle; .Z5, prepuce; .^4. glanspenis; J5, external urethral orifice; 16, pos- 

 terior branches of circumflex iliac vessels; i 7, saphenous vessels; i5, fold of flank; JP, penis (cut) ; A, superficial ingui- 

 nal lymph glands; B, prefemoral lymph glands; C, deep inguinal lymph glands. The testicle (on the right side) has 

 been rotated somewhat to show the cremaster muscle. (After Schmaltz, Atlas d. Anat. d. Pferdes.) 



vein. It descends almost vertically in the femoral canal behind the sartorius 

 muscle, covered at first by the medial femoral fascia and lower down by the gracilis. 

 After passing over the insertion of the pectineus, it perforates the adductor muscle, 

 crosses in the vascular groove of the posterior surface of the femur, and is continued 



