pyramid

(pir’am-id) [Gr. rupayis]. 1. Any cone shaped eminence upon an organ. 2. The petrous bone. anterior p’s. See p’s of the medulla oblong at a. p. of the cerebellum, 4 conic projection, the central portion of the inferior vermiform proce . p. of Ferrein, any one of the intra cortical prolongations of the malpighian pyramids. Lalouette’s p., the third lobe of the thyroid body; an occasional prolongation of the upper portion of the thyroid gland, usually on the left of the median line. p. of light, a triangular reflection seen upon the membrana tympani. Malacarné’s p., the posterior end of the pyramid of the cerebellum. p. of Malpighi, any one of the conic, striated ma es which form the medulla of the kidney, the apices projecting into the calices. p’s of the medulla oblong at a, the two anterior and two posterior columns within the medulla oblong at a: the posterior ones are the gracile fasciculi. posterior p’s. See p's of the medulla oblong at a. renalp. Same as p. of Malpighi. p. of the thyroid, the third lobe of the thyroid body; Lalouette’s pyramid. p. of the tympanum, the hollow elevation in the inner wall of the middle ear which contains the stapedius. p. of the vestibule, the anterior end of the crista vestibuli. Wistar’s p’s, the sphenoid cornua, or sphenoturbinal bones.