Organ

(or'-gan). In biology, any part of the body having a determinate function; a complex of similar or di imilar cells or ti ues that perform in common one or more vital functions. O., Acce ory, an organ that has a subordinate importance in the carrying on of a particular function, but which under certain conditions may act as a substitute for an important organ. O. -albumin, the albumin that constitutes a part of the solid ti ues. O. of Bojanus, the renal organ of molluscs, found in the majority of lamellibranchs. O. of Corti. See Corti. O., Cup-shaped, one of the organs of taste in Vermes; widely scattered over them in the integument, but especially numerous at the edge of the mouth. O's., Digestive, the digestive tract and its glands. O. of Eimer, a tactile organ in the nose of the mole, consistingnal of anerve group of term i fibrils. O., Enamel, a club-shaped proce of epithelium Organ of Kimf.r, Nosh of growing from the dental ridge and forming a cap n. Nerve, e MOLB, Epithelium chlorid. (Stirling.) over the dental papilla. From it the enamel of the tooth is developed. O. of Gegenbauer, cno ol certain ciliated organs in the Pteropod a proved ORG AN A the paradidymis. O., Goblet-shaped, one of the ge rod-shaped end-organs of nerves, observed in the skin of the teleostei and sturgeons. O., Jacob son's, a short cul-de-sac extending along Stensen's duct, lined by epithelium continuous with that of the. mucous membrane. It is well developed in some lower animals, in which it is believed to have an olfacfunction. O's., Lateral: (a) Segmentally arranged, retractile sensory organs occurring among nes only in the Chietopoda. They carry sensory hairs connected on the one hand with transverse muscle fibrillae and on the other with a plexus of ganglion-cells joined by a special nerve to the ventral cord; their function is unknown. (b) A series of nerve end-organs in the " mucous canals ' ' in the head and lateral line of fishes and amphibians. O's., Mayer's, a series of slit-like depre ions on the side of the tongue of certain mammals, first discovered by C. Mayer in the African elephant; afterward found in the Uakari monkeys (Pithekia satanis); 15 slits in front of the palato-glo al fold. O's., Pelvic, those organs situated in the pelvis. O's. of Reproduction, the testicles and penis and its glands in the male, the uterus and its appendages and the vagina and its glands, in the in the female.