[Illustration: FIG. 428.--_Cynocephalus porcarius_, Chacma baboon. Ileo-colic junction and caecum. (Columbia University Museum, No. 1071.)] [Illustration: FIG. 429.--_Cynocephalus babuin_, yellow baboon; dried preparation. (Columbia University Museum, No. 89.)] [Illustration: FIG. 430.--_Cynocephalus anubis_, olive baboon. (Columbia University Museum, No. 51/1618.)] [Illustration: FIG. 431.--_Cercopithecus pogonias_, bearded monkey. Ileo-colic junction and caecum; dried preparation. (Columbia University Museum, No. 228.)] [Illustration: FIG. 432.--_Cercopithecus sabaeus_, green monkey. Ileo-colic junction and caecum. (Drawn from preparation.) (Columbia University Museum, No. 746.) 1. Ventral ileo-caecal vascular fold. 2. Dorsal ileo-caecal vascular fold. 3. Intermediate ileo-caecal non-vascular fold. ] [Illustration: FIG. 433.--_Cercopithecus campbellii_, cercopithecus monkey. Ileo-colic junction and caecum. (Drawn from preparation.) (Columbia University Museum, No. 55/1542.)] =2. Macacus.=--The caecum is of large caliber, blunt, or in some forms slightly pointed at the apex, sacculated like the colon. The two vascular folds are narrow and low, studded with epiploic appendages. The intermediate non-vascular fold is large, placed nearer to the dorsal than to the ventral vascular fold. Figs. 434-439 show the structures in _Macacus cynomolgus_, _ochreatus_, _rhesus_ and _pileatus_. Fig. 439 is from a formaline hardened situs preparation of the abdominal viscera in _Macacus cynomolgus_, the Kra monkey. [Illustration: FIG. 434.--_Macacus cynomolgus_, Macaque monkey. Ileo-colic junction and caecum; dried preparation. (Columbia University Museum, No. 19.)] [Illustration: FIG. 435.--_Macacus ochreatus_, ashy-black macaque. Ileo-colic junction and caecum; dried preparation. (Columbia University Museum, No. 11.)] [Illustration: FIG. 436.--_Macacus rhesus_, rhesus monkey. Ileo-colic junction and caecum. (Columbia University Museum, No. 1126.)] [Illustration: FIG. 437.--_Macacus pileatus_, macaque. Ileo-colic junction and caecum. (Columbia University Museum, No. 719.)] [Illustration: FIG. 438.--_Macacus sinicus_, bonnet macaque. Ileo-colic junction and caecum. (Columbia University Museum, No. 1072.)] [Illustration: FIG. 439.--_Macacus cynomolgus_, kra monkey. Abdominal viscera, hardened _in situ_. (Columbia University Museum, No. 1801.)] B. ARCTOPITHECINI. The marmosets have a long crescentic-shaped caecum, turning the concavity of the curve upwards and to the left, terminating in a blunt point. Typical forms are shown in Fig. 440, _Hapale jacchus_, Fig. 441, _Midas ursulus_, and Fig. 442, _Midas geoffrei_. [Illustration: FIG. 440.--_Hapule jacchus_, common marmoset. Ileo-colic junction and caecum. (Columbia University Museum, No. 975.)] [Illustration: FIG. 441.--_Midas ursulus_, negro tamarin. Ileo-colic junction and caecum; dried preparation. (Columbia University Museum, No. 235.)]