THE STOMACH AXD SPLEEN 227 



(section 4 below). The following structures, however, should 

 first be identified, especially the ganglia {d, e) which are likely 

 to be damaged in disturbing the peritoneum, and may advan- 

 tageously be examined first. 



(a) The superior mesenteric artery (a. mesenterica superior), 

 a second and much larger, median branch of the aorta, 

 given off a little distance behind the coeliac artery and 

 passing in the direction of the intestine. 

 {b) The suprarenal gland (gl. suprarenalis) of the left side, a 

 pale flattened body about a quarter of an inch or more in 

 length, a short distance medial to the anterior part of the 

 kidney. If the gland is halved, examination of the cut 

 surfaces will show it to be composed of a relatively thick 

 outer cortex and a central medulla. These tw^o portions, 

 despite their close association, are both developmen tally 

 and functionally distinct organs (cf. p. 132). 

 (c) The inferior caval vein (v. cava inferior), a large thin- 

 walled vessel lying to the right of the aorta. It is not 

 conspicuous if empty. 



The following ganglia lie near 



(j(j the root of the mesentery and may 



Ca^ \ be concealed by lymph nodes 



(p. 237, d) or by fat. 

 {d) The coeliac ganglion (g. coeliacum), 

 ^ "~ an unpaired, usually somewhat 



^ triangular ganglion of the sym- 



pathetic nervous system lies a short 

 Sma'3 distance in front of the superior 



Smp -- "^ mesenteric artery (Fig. 99). 



{e) The Superior mesenteric ganglion 

 (?. mesentericum superius) of the 



Fig. 99. Coeliac and superior ° _ ... 



mesenteric ganglia exposed and Sympathetic SyStCm, whlch IS alsO 



viewed from the left side, aa, '^ . . i i i i • 



abdominal aorta; ca. coeliac Unpaired, IS a CUrVCd body lymg 



artery; eg, coeliac ganglion; sma, . i* i i i • j i 



superior mesenteric artery; smg, immediately behind the SUpCriOr 



superior mesenteric ganglion; sn, , t j i t 



splanchnic nerve. mesenteric artery, its dorsal end 



projects forward on the left side of 

 that vessel and sometimes is nearly separated from the rest 



