730 LYMPHATIC SYSTEM OF THE OX AND SHEEP 



The efferent vessels run forward on the base of the udder, then mcline outward and pass 

 through the aponeuroses of the obUque abdominal muscles at the lateral edge of the rectus ab- 

 dominis, a handbreadth or more in front of the pubis. On reaching the femoral ring they follow 

 the course of the external iliac vessels to the deep inguinal gland. When the deeper gland (Ig. 

 profunda femoris) is present, some efferents go to it. Baum has recorded the remarkable fact that 

 efferents of one side may go to a supramammary or deep inguinal gland of the opposite side. 



The sacral lymph glands (Lgg. sacrales) may be subdivided into two groups.^ 



(1) The internal sacral lymph glands (Lgg. sacrales mediales) are quite in- 

 constant. When present, there is a gland on either side on the deep surface of the 

 sacro-sciatic ligament, in the fat between the ligament and the rectum or the re- 

 tractor ani. Its afferent vessels come from the pelvic m-ethra and urethral muscle, 

 the root of the penis and its muscles, the prostate, the vagina and urethra, and the 

 coccygeal muscles. The efferent vessels usually go to the internal iliac glands. 



(2) The external sacral lymph glands (Lgg. sacrales laterales) comprise one 

 or two inconstant nodes on the upper part of the outer surface of the sacro-sciatic 

 ligament. One occurs in the majority of cases at the greater sciatic foramen; the 

 other, which is further back, imder the origin of the biceps femoris, is absent on one 

 side or both in more than half the cases. Their afferent vessels come from the 

 gluteus profimdus, the lumbo-dorsal fascia, the pelvic bones, and the hip joint. 

 The efferent vessels go to the internal iliac and deep inguinal glands. 



The ischiatic lymph glands (Lgg. ischiadicee) are one or two in number. The 

 one which appears to be constant lies on the sacro-sciatic ligament, about an inch 

 (ca. 2-3 cm.) above the lesser sciatic notch, and under cover of the biceps femoris. 

 It is discoid and is an inch or more (ca. 2.5-3.5 cm.) in diameter. A second gland 

 occurs in the majority of cases at the medial side of the tuber ischii and the attach- 

 ment of the sacro-sciatic ligament, covered only by the skin and subcutaneous fat.^ 

 The afferent vessels come from the rectum and anus; the vulva, the root of the 

 penis, the prostate, the bulbo-urethral glands, the urethra and urethral muscle; 

 the glutei, biceps femoris, semitendinosus, obturator internus, and gemellus, and 

 the lumbodorsal fascia; the skin of the hip and tail; the hip joint. They also 

 receive efferent vessels of the popliteal gland. The efferent vessels go to the internal 

 iliac glands.^ 



The gastric lymph glands (Lgg. gastricse) are numerous, as might be expected, 

 and are difEcult to group satisfactorily. They comprise the following: 



(1) The atrial lymph glands (Lgg. atriales) lie chiefly on the visceral surface 

 of the atrium, just behind the cardia; commonly three or four are present. Their 

 afferent vessels come from the atrium, from the adjacent part of the rumen and 

 reticulum, and from the spleen. They receive efferent vessels of the right and 

 anterior ruminal, reticular, omasal, and dorsal abomasaJj glands. Their efferent 

 vessels commonly converge to a large trunk, the common efferent vessel (Vas 

 efferens commune) of the gastric lymph glands. This runs upward and backward 

 in relation to the cceliac artery and reaches the ventral face of the posterior vena 

 cava; here it unites with the common efferent vessels of the mesenteric glands to 

 form t^e intestinal trunk. 



(2) The right nuninal lymph glands (Lgg. ruminales dextrse) lie along the 

 course of the right ruminal artery. Commonly four or five are present, and they 

 are half an inch to an inch and a half (ca. 1-3.5 cm.) long. Their afferent vessels 

 come chiefly from the rumen. They also receive efferent vessels of the other 

 rimiinal glands. The efferent vessels go from the anterior part of the series to the 

 reticular glands and the conunon gastric efferent. 



^ Baum distinguishes three groups of sacral glands and terms the glands about the termina- 

 tion of the aorta and the origin, of the vena cava as the lgg. sacrales hypogastricae. These have 

 been included in the internal iliac group of this description'. 



^ This gland is termed by Baum the Ig. tuberosa. 



' Many variations occur in the' arrangement of those efferent vessels. An efferent may go", 

 to a coeliac or mesenteric gland or to the intestinal trunk or cistema chyli directly. 



