2. Gorilla savagei, Gorilla (Fig. 457).—The cæcum is large, distinctly sacculated, presenting a decided curve with the concavity directed toward the left. The appendix is implanted at the center of the blunt apex of the pouch, the cæcal sacculations on each side of the root of the appendix being of nearly equal size (folds and fossæ, cf. [p. 269]).
Fig. 458.—Simia satyrus, orang. Cæcum and ileo-colic junction; ventral view. (Drawn from Columbia University Museum preparation No. 716.) 1. Appendix. 2. Ventral vascular fold.
Fig. 459.—Simia satyrus, orang. Cæcum and ileo-colic junction; dorsal view. (Drawn from Columbia University Museum preparation No. 716). 1. Appendix. 2. Intermediate non-vascular fold.
3. Simia satyrus, Orang-outang.—Figs. 458 and 459 represent respectively the ventral and dorsal views of the cæcum and ileo-colon in a nearly adult male specimen of orang, about 4½ feet high.
The cæcum is funnel-shaped, gradually narrowing to the origin of the appendix from its apex, which is carried upwards to the left by the well-marked crescentic curve of the pouch. The sweep of the funnel to the left and upwards is characterized by the curved course of the ventral longitudinal muscular band (Fig. 458), whose fibers spread out over a surface 3 cm. wide. The apex is thus placed behind the terminal ileum close to its entrance into the large intestine.
At the level of the upper margin of the ileo-colic junction the narrow pointed termination of the cæcum passes gradually into the beginning of the appendix (Fig. 459).
The appendix measures along its free border 22.6 cm. It follows the direction of the cæcal curve for 2.7 cm., at which point it appears somewhat constricted and takes an abrupt bend downwards for 4.3 cm.; curving again upwards for 7.5 cm., it turns downward a second time for 5.4 cm. and terminates in a hook-like extremity 2.7 cm. long (Fig. 459).