1. Immediately after rotation the large intestine lies transversely along the greater curvature of the stomach, with the cæcum on the right side in front of the duodenum and closely applied to the caudal surface of the right lobe of the liver (Fig. 147).

Persistence of Subhepatic Position of Cæcum in Adult.—The period at which the cæcum descends into the iliac fossa is liable to a considerable range of variation.

Treves found in two fœtus, measuring respectively 4½″ and 5½″, the cæcum on a level with the caudal end of the right kidney, while in several individuals at full term the caput coli was still placed immediately below the liver, with no large intestine in the place of the ascending colon. This condition is well illustrated in the fœtus shown in [Fig. 124].

The cæcum may remain undescended throughout life. Treves, in an examination of 100 bodies, found this condition in two subjects, both females, one 41, the other 74 years of age. Both cases presented an identical disposition. There was no large intestine in the place of the ascending colon. The cæcum was placed on the right side, immediately underneath the liver, just to the right of the gall-bladder; it was quite horizontal in position, continuing the long axis of the transverse colon and included between the layers of the transverse mesocolon. From the extremity of the cæcum a horizontal fold was continued to the abdominal parietes and upon it the edge of the liver rested. In one of these instances the colon from the tip of the cæcum to the splenic flexure measured 38″. The great omentum was attached only to the left half of this portion. The descending colon was very long, measuring 15″.

In the other case the distance from the tip of the cæcum to the splenic flexure was 27″, the great omentum commencing 5″ from the former point. The descending colon was of normal length.

In both bodies the remaining viscera were normal.

2. The cæcum next descends ventrad of right kidney to the iliac fossa. The future ascending colon is at this time placed very obliquely on account of the large size of the fœtal liver, and passes without a marked angle into the transverse segment. Thus in Fig. 148, from a fœtus 5″ in length, the descending colon is vertical and the splenic flexure well marked, forming the highest point of the colic arch. There is no hepatic flexure, and no ascending and transverse colon, but instead of these an oblique segment passing upwards and to the left between cæcum and splenic flexure.

This disposition, due to the large size of the liver, is still marked at times in the fœtus at term, and occasionally even in children up to 2 or 3 years of age.

Fig. 148.—Abdominal viscera of human fœtus of 12.5 cm., vertex-coccygeal measure, hardened in situ; transverse and ascending colon not yet differentiated. (Columbia University Museum, No. 1815.) Natural size.   Fig. 149.—Abdominal viscera of human fœtus at term, hardened in situ; hepatic flexure formed and ascending and transverse colon differentiated. (Columbia University Museum, No. 1816.)

3. The ascending colon is subsequently differentiated from the transverse segment and the hepatic flexure formed consequent upon the diminution of the relative size of the liver, which permits the fœtal oblique segment of the colon extending in the earlier stages between the right iliac fossa and the spleen to become divided by a right-angled (hepatic) bend or flexure into an ascending and a transverse segment (Fig. 149).