452 CHARLES F. SILVESTER 



pithecus trivirgatus, or with a single opening into the left renal 

 vein, as was the case in one specimen of Ateles atar. The single 

 intestinal trunk may open in common with the right lumbar 

 trunk into the cranial surface of the left renal vein (fig. 6, Cebus 

 hypoleucus), or with the left lumbar trunk into the caudal sur- 

 face of the left renal vein (Cebus hypoleucus, 2474). In one 

 specimen of Midas oedipus (fig. 10) the single truncus intestinahs 

 split into three branches and opened, one branch into the ven- 

 tral surface of the postcava, the other two into the left renal vein. 

 The intestinal lymphatics may form a network with as many as 

 four openings into the veins (Ateles vellerosus, fig. 3 and Ateles 

 variegatus, fig. 2) There may be three trunks present, two open- 

 ing into the postcava and one into the renal vein (No. 2493, 

 Cebus hypoleucus), or two into the left renal vein and one into 

 the postcava (Cebus hypoleucus, 2471). 



In many instances anastomoses occur between the mesenteric 

 and the lumbar lymphatic trunks. These are shown in their 

 more complicated form in fig. 2 (Ateles variegatus). A simple 

 joining of the two trunks, forming what may be termed a mesen- 

 terico-lumbar communication, occurred in one specimen of Cebus 

 hypoleucus (2474). In this individual the mesenteric trunk 

 divides on each side of the left sex-vein and opens with the left 

 lumbar trunk into the caudal surface of the left renal vein. 



2. Communications between the lumbar lymphatic trunks and 

 the veins. The lymphatico-venous communications of the ves- 

 sels from the posterior extremities and lumbar regions present 

 quite as many, or even more variations in regard to position and 

 number than do those of the mesenteries. They vary in number 

 from two to as many as five openings and may be situated at 

 almost any point or combination of points on the veins of the 

 renal region. The variations in the position and number of these 

 communications were found to be so great that the writer has 

 been unable to find any two individuals possessing the same 

 arrangement. In general it might be stated that the lumbar 

 trunks of the right side open either into the postcava, or at the 

 juncture of the postcava and the left renal vein, and that those 

 of the left side open into the left renal vein. 



