3. _The colon on each side of the ileo-colic junction is prolonged backward along the small intestine, forming two symmetrical lateral globular colic caeca._ This type, which is to be regarded as a further development of the preceding form, is also found in the armadillos. Fig. 359 represents the structures in _Dasypus sexcinctus_, the six-banded armadillo, and a similar arrangement of the parts exists in _Chlamydophorus_, another species of armadillo. [Illustration: FIG. 359.--_Dasypus sexcinctus_, six-banded armadillo, Ileo-colic junction and caeca. (Columbia University Museum, No. 1478.)] 4. _The caecal pouches are more completely differentiated, communicating with the colon by a constricted neck._ This results in an arrangement which recalls the structure of many avian caeca (cf. Fig. 337) and is seen in the double caecal pouches of _Cyclothurus didactylus_, the little ant-eater (Fig. 360). [Illustration: FIG. 360.--_Cyclothurus didactylus_, little ant-eater. Ileo-colic junction and caeca. (Columbia University Museum, No. 1512.)] II. ASYMMETRICAL TYPE OF ILEO-COLIC JUNCTION. The second general group of the Edentates is characterized by the gradual development of a single lateral asymmetrical caecum, in place of the median symmetrical ileo-colic transition found in the forms just considered. The species composing this group thus form a link leading up to the right-angled accession of ileum to large intestine and the lateral caecum characteristic of most other mammalia. [Illustration: FIG. 361.--_Manis longicauda_, long-tailed pangolin. Ileo-colic junction; dry preparation. (Columbia University Museum, No. 95.)] [Illustration: FIG. 362.--_Manis longicauda_, long-tailed pangolin. Ileo-colic junction. (Columbia University Museum, No. 328.)] 1. This type may be considered as being inaugurated by the form of ileo-colic junction found in the _Manidae_ or _Pangolins_, as illustrated by Figs. 361 and 362, taken from the long-tailed pangolin, _Manis longicauda_. There is no caecum and only a slight differentiation in caliber between the small and large intestine. The gut in all the forms examined shows a very characteristic bend at the ileo-colic junction, being twisted into a figure of 8 and held in place by mesenteric folds. [Illustration: FIG. 363.--_Arctopithecus marmoratus_, three-toed sloth. Ileo-colic junction. (Columbia University Museum, No. 1479.)] 2. The second stage, illustrated by _Arctopithecus (Bradypus) marmoratus_, the three-toed sloth (Fig. 363), reveals a distinct increase in the caliber and convexity of the large intestine opposite the mesenteric border immediately beyond the ileo-colic junction. [Illustration: FIG. 364.--_Tamandua bivittata_, Tamandua ant-eater. Ileo-colic junction and caecum. (Columbia University Museum, No. 1590.)] [Illustration: FIG. 365.--_Tamandua bivittata_, Tamandua ant-eater. Ventral view of abdominal viscera from the left side. (Study Collection, Columbia University.)]