PLEXUS 



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PLEXUS 



of origin of the median nerve given off by the eighth 

 cervical nerve. Syn., Pes anserinus nervi mediant. 

 P., Arnold's Ground, a plexus formed by the axis- 

 cylinders of nonmedullated nerve-fibers in smooth mus- 

 cular tissue. P., Basilar, P. basilaris, of Virchow, 

 the transverse sinus. P., Bulbocavernous, P. bulbo- 

 cavernosus, branches of the pudendal plexus located 

 in the region of the urethra. P. capitis, one formed 

 over the epicranium by the junction of branches of the 

 trigeminal nerve and upper cervical nerves. P., Car- 

 diac Superior. See P., Cardiac Posterior (Illus. 

 Diet.). P. cardiacus inferior. See P. , Cardiac 

 Anterior (Illus. Diet.). P., Carotid, P. caroticus, 

 the internal carotid plexus. P., Carotid Common, 

 P. caroticus communis, one formed of sympathetic 

 fibers about the common carotid artery. P. cervico- 

 brachialis, the cervical and brachial plexus re- 

 garded as one. P. chorioideus foraminis inter- 

 ventricularis. See Auliplexus or Portiplex (Illus. 

 Diet.). P. chorioideus impar. See P., Choroid 

 (Illus. Diet.). P. chorioideus interpositus, a fold 

 of the pia lying between the choroid plexuses of the 

 lateral ventricles. P. chorioideus lateralis, the para- 

 plexus. P. chorioideus medius, the diaplex. P., 

 Choroid, Inferior, P. chorioides cerebelli. See 

 Metaplexus (Illus. Diet.). P., Choroid Lateral, 

 P. chorioidei laterales. See Paraplexus (Illus. 

 Diet.). P., Choroid Median, the diaplex. P. 

 chorioides cerebri. See Diaplex (Illus. Diet.). P. 

 chorioideus ventriculi lateralis. See Paraplexus 

 (Illus. Diet.). P. chorioideus ventriculi quarti. 

 See Metaplex (Illus. Diet.). P. chorioideus ventri- 

 culi tertii. See Diaplex (Illus. Diet.). P. chorioid- 

 eus telencephali. See Prosoplexus (Illus. Diet. ). P. 

 circularis foraminis magni, that part of the occipital 

 sinus extending around the edge of the foramen magnum 

 to the jugular foramen. Syn., Marginal sinus. P.s, 

 Colic, the divisions of the mesenteric plexuses which 

 accompany the colic arteries. P. coronarius dexter. 

 See P., Coronary Anterior (Illus. Diet.). P. coro- 

 narius sinister. See P., Coronary Posterior (Illus. 

 Diet.). P., Cruveilhier's. (See Illus. Diet. ) 2. 

 The plexus of varicose veins constituting one of the 

 varieties of angioma. P., Deep. See Cardiac, Great 

 (Illus. Diet.). P., De'ferential, P. deferentialis, 

 the extension of the vesical plexus supplying the vas 

 deferens, the seminal vesicle, and half of the prostate. 

 P., Dorsispinal, the dorsispinal veins and their inter- 

 communications. P. entericus. See P., Meissner's 

 (Illus. Diet. i. P., Exner's, a layer of nerve-plexuses, 

 probably formed by the junction of sensory and motor 

 fibers, in the cerebral cortex, near the surface. P., 

 Extraspinal, the network formed by the dorsispinal 

 veins. P., Facial, one around a portion of the facial 

 artery. P., Femoral, the lumbar plexus. P., 

 Femoral, Inferior. See /'., Sacral (Illus. Diet.). 

 P., Gangliform Semilunar, the celiac plexus. P., 

 Gerlach's. See Gerlac/i's Network ( Illus. Diet. ). 

 P., Great. See P., Deep. P. gustatoriosensorius, 

 one in the tongue made up of branches from the glos- 

 sopharyngeal and gustatory nerves. P., Guttural. See 

 /'., Pharyngeal Illus. Diet). P., Haller's Laryn- 

 geal, the network formed by branches of the external 

 laryngeal and sympathetic nerves on the outer surface of 

 the inferior constrictor pharyngis. P. hederaceus. See 

 /'., Pampiniform (Illus. Diet.). P., Heller's, the net- 

 work of arteries in the deeper layer of the intestinal 

 submucosa. P., Hovius' See /'., Leber" 1 s. P., 

 Ileocolic, the division of the superior mesenteric 

 plexus which accompanies the ileocolic artery. P., 

 Inframaxillary. See P., Dental, Inferior (Illus. 

 Diet.). P., Infrathyroideal, Cloquet's name for the 



one formed ventrad of the trachea by the anastomosis 

 between the branches of the right and left inferior 

 thyroid veins. P., Interepithelial, the network of 

 nerves between the cells of the corneal epithelium. 

 P. intermeseraicus. See P., Aortic (abdominal) 

 (Illus. Diet.). P., Interpterygo.id, that portion of 

 the pterygoid plexus lying between the external and 

 internal pterygoid muscles. P., Intraepithelial, the 

 network formed by the ultimate fibrils of the subepithe- 

 lial plexus distributed among the epithelial cells of the 

 cornea. P., Intraspinal, the venous network sur- 

 rounding the spinal canal and opening into the lum- 

 bar, vertebral, intercostal, and lateral sacral veins. P., 

 Jugular, a reticulum of lymphatics and glands on the 

 lateral aspect of the neck. P., Jugular, Deep, a 

 lymphatic plexus below the base of the skull lying 

 upon the internal jugular vein. P., Jugular, Super- 

 ficial, a name for the lymphatics coming from the ear, 

 temple, and occiput, opening into the vessel that ac- 

 companies the internal jugular vein. P., Laryngeal, 

 a network of the branches of the sympathetic and ex- 

 ternal laryngeal nerves situated on the outer aspect of 

 the inferior constrictor of the larynx. P., Leber's, a 

 plexus of venules in front of Schlemm's canal, with 

 which it communicates. P., Lumbosacral, the lum- 

 bar, sacral, and coccygeal plexuses taken as one. P. 

 magnus profundus, Scarpa's name for the deep car- 

 diac plexus. P., Mammary, Internal, P. mam- 

 marius internus, the sympathetic plexus surrounding 

 the internal mammary artery. P., Median, the celiac 

 plexus. P., Meissner- Billroth's. See P., Jl/e/ss- 

 ner' s (Illus Diet.). P., Meningeal, P. meningeus 

 medius, the sympathetic plexus on the middle men- 

 ingeal artery ; it is a continuation of that on the ex- 

 ternal carotid. P., Molecular, the reticulum of 

 myelonic and amyelonic nerve-fibers in the outermost 

 layer of the cerebral cortex. P., Musculointestiral, 

 P., Myenteric, External, P. myentericus externus. 

 See P., Auerback's (Illus. Diet.). P., Myenteric, 

 Internal, P. myentericus internus. See P., Meiss- 

 ner's (Illus. Diet.). P. nervi vagi, the lateral part 

 of the metaplexus. P., Omental, the gastroepiploic 

 plexus. P., Opisthogastric, the solar plexus. P., 

 Ovarian, Inferior, a nerve plexus lying between the 

 folds of the broad ligament and giving off branches to 

 the ovary and round ligament. P.s, Panizza's, two 

 lymphatic plexuses lying in the lateral fossa of the 

 preputial frenum ; they are formed by the deeper lym- 

 phatic vessels of the integument of the glans penis. 

 P.s, Pneumogastric, the anterior and posterior pul- 

 monary plexus and the esophageal plexus. P., Poly- 

 morphic, a nerve plexus in the fourth layer of the cor- 

 tex. P., Popliteal, P. popliteus, a sort of plexus 

 around the popliteal artery formed by the small 

 branches of the anterior crural nerve. P.s, Preaortic, 

 a comprehensive term for the plexuses of the sym- 

 pathetic lying near to and ventrad of the aorta, e. g., 

 the pharyngeal plexus, solar plexus, posterior pul- 

 monary plexus. P.s, Prevertebral. See P., Solar, 

 P., Cardiac, and P., Hypogastric (Illus. Diet.). P., 

 Prostaticovesical, the pudendal plexus of veins. P., 

 Pterygoid, External, the superficial part of the ptery- 

 goid plexus of veins; it receives the buccal and mas 

 seteric veins. P., Pterygoid, Internal, the dorsal 

 part of the pterygoid plexus of veins. P. pubicus 

 impar, the pudendal plexus of veins. P. pubicus 

 par, veins passing on each side of the pudendal plexus 

 to the plexus bulbo-cavernosus. P., Pudendocaudal,. 

 the pudendal and coccygeal considered as one. P. 

 pudendohaemorrhoidalis, P. pudendovesicalis, P. 

 pudendus, the pudendal plexus of veins. P., Rami- 

 form, P. ramiformis, a plexus formed by the fibers 



