_Macacus cynomolgus_, ileo-colic junction and caecum of, 214 descending mesocolon of, 140 lesser omentum of, 176 mesosigmoidea in, 140 _nemestrinus_, cheek-pouches of, 48 _ochreatus_, ileo-colic junction and caecum of, 214 peritoneum of infra-colic compartment, 136 _pileatus_, ileo-colic junction and caecum of, 214 relations of spleen and great omentum, 139 _rhesus_, abdominal viscera, 77 ileo-colic junction and caecum of, 214 Mammalia, ileo-colic junction of, 204 pancreatic ducts in, 117 _Manatus americanus_, ileo-colic junction and bifid caecum of, 208 stomach of, 48 _Manis longicauda_, ileo-colic junction of, 208 Manidae, colic bend of, 234 Marsupalia, ileo-colic junction of, 204 types of ileo-colic junction and caecum in, 218 Meckel's diverticulum, 35 serous folds connected with, 262, 263 Medullary canal, 21 groove, 21 plates, 21 Membrane, cloacal, 24 Mesenchyma, 30 Mesenteric peritoneum, definition of, 32 Mesentery, absorption of, 33 definition of, 101 jejuno-ileal, line of attachment, 86 of umbilical loop, development of, 56 relation to adult mesocolon and mesentery, 72 Mesoblast, 21 Mesocola in cat, 86 Mesocolic fossa, 97 Mesocolon, ascending, adhesion of, 82 in monkeys, 83 relation of, to right kidney, 83 definition of, 101 descending, adhesion of, 82 in foetus, 83 line of attachment of, 83 in lower mammals, 83 in _Macacus_, 140 in monkeys, 83 transverse, root of, 85 Mesoderm, 21 derivatives of, 28 Mesoduodenum, adhesion of, 67 definition of, 101 Mesorectum, definition of, 101 Mesosigmoidea, definition of, 101 in _Macacus_, 140 Mesothelium, 21 Metanephros, 24 _Midas geoffrei_, ileo-colic junction and caecum of, 214 _ursulus_, ileo-colic junction and caecum of, 214 Midgut, 192 extent of, 38 _Monodon_, ileo-colic junction of, 209 Monotremata, ileo-colic junction of, 204 Monotreme, structure of penis, 26 Monotremes, biliary ducts in, 145 Morphology, general, of vertebrate intestine, 190 of human caecum and appendix, 237 Morula, 20 _Moschus_, stomach of, 49 Muscular stomach of birds, 50 Musculo-cutaneous vein in Anure Amphibian, 158 _Mustela_, ileo-colic junction of, 212 _Mycetes cobaya_, ileo-colic junction and caecum of, 214 _fuscus_, ileo-caecal folds of, 264 ileo-colic junction and caecum of, 215 _Myoxus_, alimentary canal of, 211, 212 stomach of, 46 _Myrmecophaga jubata_, ileo-colic junction of, 207 _Myxinoids_, pancreas in, 117 _Nasua rufa_, duodenal fold of, 92 ileo-colic junction of, 212 pancreatico-gastric folds of, 181 _Necturus_, alimentary canal of, 40 _maculatus_, alimentary tract of, 52 ileo-colic junction of, 201 stomach of, 43 venous system of, 158 Neuro-enteric canal, 23