360 ANATOMICAL TECHNOLOGY. 



of the M. psoas ; it is, however, partly covered by the adrenal and the cephalic end of the 

 kidney. It will be necessary to remove the fat and connective tissue with great care from 

 the adrenal and phrenic arteries, and it may be desirable to use the forceps and scissors to 

 remove tough connective tissue and nerves. As was stated above, the A. phrenica may be 

 supplied by the cceliac axis (§ 966). The left A. adreuo-lumbalis much more often sup- 

 plies an A. phrenica than the right. The left and its branches are more easily demon- 

 strated than the right. 



§ 969. A. renalis (Fig. 101, 103, 107).— The renal artery arises 

 from the side of the aorta like the preceding, and passes nearly lat- 

 erad to enter the hilum of the kidney. It usually gives from its 

 ventral surface a small branch to the adrenal, and often one to the 

 ureter. The renal artery is covered on its ventral surface by the 

 Y. renalis ; hence, to obtain a good view of the artery, the vein 

 must be removed or drawn aside. Employ the tracer, working care- 

 fully in order that the branches named above may not be broken. 



The A. renalis usually divides into two nearly equal branches 

 about 1 cm. from the kidney, and one branch goes to each side of 

 the renal pelvis ; it is sometimes double (Fig. 103). 



§ 970. A. spermatica (male), ovarii (female), (Fig. 101). — This arises from the ven- 

 tral surface of the aorta 1-2 cm. caudad of the A. renalis. It passes somewhat obliquely 

 caudad, supplying the ovary in the female and forming part of the spermatic cord in 

 the male. 



Expose it by turning the intestines to the right ; then very carefully tear away the 

 peritoneum covering the aorta. As the artery is only about 1 mm. in diameter, great care 

 is necessary in the dissection ; probably it will be necessary to employ the forceps and 

 scissors as well as the tracer. In the female the artery is much convoluted ; see § 960. 



§ 971. A. mesenterica inferior, az. (Fig. 101, 103, 107).— The 

 artery arises from the ventral surface of the aorta about opposite 

 the iliac crest (Fig. 51). It passes nearly ventrad. 



Turn the large intestine to the right, and with the tracer follow 

 it. Near the large intestine it divides into two branches : — 



(A) A. colica sinistra, which extends cephalad aJong the large 

 intestine and anastomoses with the A. colica media (§ 967, B). 



(B) A. hsemorrhoidalis superior. This passes caudad along the 

 large intestine and anastomoses with the hsemorrhoidalis media from 

 the A. iliaca interna. 



§ 972. A. ilio-lumbalis (Fig. 101). — This artery arises from the side of the aorta 

 slightly caudad of the origin of the preceding (§ 971), and passes laterad over the ventral 

 wall of the M. psoas, and to other muscles over and near the Ilium. It is comparable 

 with the A. adreno-lumhnlis (§ 968). To demonstrate it, turn the large intestine to the right, 

 and tear away the peritoneum with a tracer. As it is the only artery passing laterad in 

 this region, it cannot be mistaken. 



