MEDULLARY a.
ch unite, making a tube (the medullary canal) from which the brain and spinal cord are developed. -- Medullary rays (Bot.), the rays of cellular tissue seen in a transverse section of exogenous wood, which pass from the pith to the bark. -- Medullary sheath (Anat.), the layer of white semifluid substance (myelin), be…
MESENTERON n.
All that part of the alimentary canal which is developed from the primitive enteron and is lined with hypoblast. It is distinguished from the stomod, a part at the anterior end of the canal, including the cavity of the mouth, and the proctod, a part at the posterior end, which are formed by invagination and are lined w…
MOUNTAIN a.
untainous; vast; very great. The high, the mountain majesty of worth. Byron. Mountain anthelope (Zoöl.), the goral. -- Mountain ash (Bot.), an ornamental tree, the Pyrus (Sorbus) Americana, producing beautiful bunches of red berries. Its leaves are pinnate, and its flowers white, growing in fragrant clusters. The Euro…