Maxil´la, n. Jaw, especially the upper jaw, or maxilla superior; the maxilla inferior being especially called mandibula. (10.)

Max´illar, Max´illary, a. Pertaining to the upper jaw. Maxillary bone, the cheek-bone; in birds an inconsiderable bone of the bill itself, not of the cheek.

Max´illo-pal´atine (bone), n. Certain paired bone of the upper jaw in the palate.

Mea´tus, n. Passage or canal. Meatus auditorius, ear-passage.

Me´dian, a. Lying in the middle line. Opposed to lateral.

Mediasti´num, n. One of the thoracic partitions.

Medul´la, n. Marrow. Medulla spinalis, spinal cord. Medulla oblongata, tract of nerve matter between cerebellum and spinal cord proper.

Mel´anism, n. State of coloration resulting from excess of black or dark pigment; a frequent condition of hawks.

Melanis´tic, Melanot´ic, a. Affected with melanism.

Mem´brana Putam´inis, n. The lining membrane of the egg-shell, formed of dense modified albumen.