system (sis'tem). 1

A methodical arrangement of organisms, etc., according to their relationships. 2. A group or aggregation of organs or structures having special functions. alimentary s. See gastroenteric s. a ociation s. A s. of a ociation fibers, callosal s. The s. of nerve fibers in the corpus callosum which, according to Meynert and Arnold, unite symmetrical regions in the two hemispheres, cardiovascular s. The heart and blood ve els, central nervous s. The brain and spinal cord, circulatory s. See cardiovascular s. commi ural s. See trabecular s. extra spinal ganglionic s. Of M. Hall, the sympathetic nervous ganglia situated on each side of the spine, first a ociation s. The s. of a ociated fibers connecting the optic thalamus with the cortex cerebri, first projection s. Of Meynert, those tracts of nerve fibers which extend between the great ganglionic ma es of the brain and the convolutions. They include a portion or the whole of the corona radiata. ganglionic nervous s. See sympathetic (nervous) s. gastroenteric s., gastrointestinal s. The alimentary tract from the lips to the anus, gastrovascular s. A s. having both digestive and circulatory functions, genito-urinary s. The urinary and reproductive organs. havers i an s. An havers i an canal with its lamellae, lacunae, and canaliculi. lymphatic s. The lymph ve els and nodes. lymph canalicular s. Intercommunicating lymph cavities in the connective ti ue of organs continuous with the lymphatic capillaries, middle s. of the florae arCuatae. The arciform fibers connected with the corpus dentatum olivae. They form its capsule, and then enter it, being connected, according to Meynert, with its nerve cells, nervous s. The brain, spinal cord, sympathetic nervous s., and nerves, organic nervous s. See sympathetic (nervous) s. projection s. The sensory nerve fibers of the body which terminate in the cortex, pa ing through the central tubular gray matter after converging from the crura cerebri, primarily derived from peripheral sensory nerves; so-called because an image of the external world is considered as projected upon the cerebral cortex by the aid of this s. respiratory s. The lungs and air-pa ages. spinal s. of nerves. The nerves originating from the spinal cord in distinction with those having a cranial origin. superior s. of the florae arcuatae. The upper bundles of arcuate fibers of the medulla oblong at a. sympathetic (nervous) s. The sympathetic nerves and ganglia and the plexuses connected with them, trabecular s., transverse a ociating s. Those bundles of nerve fibers (e. g., the corpus callosum and the anterior commi ure) which connect similar regions of the opposite hemispheres of the brain, vascular s. The s. of ve els concerned in the circulation of the blood. [Gr., system a, syn, with, together, + istana i, to set, to arrange.]