PLEXUS 



4-23 



PLURIFETATION 



of two or more nerve trunks. P., Ranvier's. See 

 P. , Stroma, Superficial. P., Ranvier's Acces- 

 sory, the superficial stroma plexus of the cornea. P., 

 Reticular. I. The choroid plexus. 2. The bulb 

 of the vestibule. P. retiformis, the bulb of the vesti- 

 bule. P., Sacral, Anterior. See P., Sacral (Illus. 

 Diet.). 2. The venous plexus on the ventral aspect 

 of the sacrum. P., Sacral, Lymphatic, a plexus of 

 lymphatic vessels in the hollow of the sacrum. P., 

 Sacral, Posterior. 1. One formed by the sacral 

 veins on the dorsal aspect of the sacrum. 2. Une 

 formed by the posterior branches of the two lower lum- 

 bar and sacral nerves dorsad of the sacroiliac articula- 

 tion. P. sacrococcygeus, the coccygeal plexus. 

 P., Sacrolumbar. See P., Lumbosacral. P., 

 Sciatic. See P., Sacral tlllus. Diet. i. P. simpli- 

 cissimus, an anastomosis between two nerve trunks, 

 in which only one gives out fibers. P., Stenon's, a 

 venous plexus encircling Stenon's duct. P., Stroma, 

 the plexus of axis-cylinders formed by the nerves of 

 the cornea. P., Stroma, Deep, that formed by the 

 deeper series of nerves entering the cornea from the 

 sclerotic and distributed between the laminas of the 

 mesocornea. P., Stroma, Superficial, that formed 

 by the superficial series of nerves entering the cornea 

 from the sclerotica and proceeding to the ectocornea, 

 where they form the subepithelial plexus. Syn., Ran- 

 zier's plexus. P., Subarachnoid, one formed oc- 

 casionally over the pia by the union of small inconstant 

 branches of spinal nerve roots. P., Subcutaneous, 

 of the Abdomen, the venous ramifications on the 

 ventral abdominal wall. P., Subepithelial, the 

 reticulum formed by the terminal filaments of the 

 ciliary nerves beneath the corneal epithelium. P., 

 Sublingual, the reticulum formed by the interlacing 

 of the branches of the lingual nerve supplying the 

 sutJingual gland. P., Submolecular, one in the 

 small pyramidal-cell layer of the cortex. P., Sub- 

 mucous, P. submucosus, Meissner's plexus. P., 

 Subpleural Mediastinal, one situated beneath the 

 pleura made up of branches of the internal mammary 

 artery and those from the superior phrenic, bronchial, 

 and intercostal arteries. P., Supraclavicular, a 

 plexus of lymphatics near the subclavian vessels. P., 

 Temporal, Superficial, a plexus derived from the 

 external carotid plexus attending the branches of the 

 external carotid artery 10 the eyelids and the external 

 ear. P., Testicular, P. testicularis, the spermatic 

 plexus. P. thyroideus impar, a venous reticulum 

 formed by the inferior thyroid veins ventrad of the 

 trachea. P., Transverse Anterior, a plexus formed 

 by stnai I transverse veins in the vertebral canal lying 

 between the posterior common ligament and the dorsal 

 surface of the bodies of the vertebras. P.. Triangular, 

 a network formed by the sensory root of the trigeminal 

 nerve on the gasserian ganglion. P., Uterine, An- 

 terior, a network formed by branches from the inferior 

 hypogastric plexus distributed to the cervix and the 



I ventral surface of the uterus. P.. Uterine, Com- 

 mon, P. uterinus communis, the hypogastric plexus. 

 P., Uterine. Great, P. uterinus magnus. 1. The 

 hypogastic plexus in the female. 2. The lower part 

 of the hypogastric plexus. P., Uterine, Posterior, a 

 plexus of nerves derived from the hypogastric plexuses 

 and distributed to the lateral and dorsal surfaces of the 

 uterus. P., Uterine, Superior, the pelvic plexus. 

 P. uterinus lateralis inferior. P., Uterine, Inferior. 

 See /'., Uterine, Anterior. P. uterinus lateralis 

 superior. See P., Uterine, Posterior. P. uterinus 

 venosus, the uterine plexus of veins. P. vasis 

 deferentis. See P. deferentinlis. P. venae portae, 

 P. venae portarum, a network on the portal vein 



formed by the branches of the hepatic plexus. P. 

 venosus, any plexus of veins. P. vesicae felleae, 

 the cystic plexus. P., Vesicovaginal, a reticulum 

 formed by the filaments of the pelvic plexus supplying 

 the inferior part aud side of the bladder and the adja- 

 cent part of the vagina. P. vesiculae seminalis. 

 See /'. de/erentialis. P., Walther's Arterioso- 

 nervous, the cavernous plexus. 

 Pli {pie) [Fr.]. I. A gvrus or convolution. 2. A 



fold. 3. Plica. 

 Plica. (See Illus. Diet.) 4. The same as P. polonica. 

 5. A ridge. P. triangularis, a triangular-shaped 

 membrane which has been termed the capsule or oper- 

 culum of the tonsil ; first described by His in 1885. 

 It arises from the anterior pillar and becomes visible 

 at the fifth month of fetal life, and in a typical case 

 extends from the upper posterior portion of the pillar 

 backward and downward until it is finally lost in the 

 tissues at the base of the tongue. P. ureterica. See 

 Bar, Mercier s. P. Vateri, P. verticalis duodeni. 

 See Ampulla of Voter (Illus. Diet). 

 Plicadentin ( pli - kah - den' -tin). See Plicidentine 



(Illus. Diet). 

 Plomb (plum) [Fr. plomber, to plug a tooth]. A filling 

 for a cavity. P., Iodoform (of Mosetig-Moorhof ), 

 an antibacillary agent used for filling bone cavities 

 after operations for tuberculosis or osteomyelitis. It 

 consists of iodoform, 40 parts, spermaceti and oil of 

 sesame, each 30 parts. The menstruum is sterilized 

 thoroughly by boiling ; the finely powdered and sterilized 

 iodoform is added slowly to the mixture and agitated 

 constantly until it cools off, to insure a uniform dis- 

 semination of the iodoform throughout the mass, which 

 solidifies at an ordinary temperature. After the cavitv 

 is prepared the mixture is heated and in a fluid state 

 is poured into it, when it again becomes firm and fills 

 the cavity like dentists' amalgam in aearious tooth (N. 

 Senn). 

 Ploration (plo-ra'-shun) [plot are, to weep]. Lacrima- 



tion. 

 Plug. (See Illus. Diet.) P.s, Fungoid, P. s, Traube's. 

 See P.s, Dittricfis (Illus. Diet.). P., Imlach's 

 Fat. See under Imlach. 

 Plugger { plug'-ur) [D. plug, a bung]. An instru- 

 ment for the insertion and impacture of filling materials 

 in cavities in teeth. P., Electric, an instrument in 

 which an interrupted current magnetizes electro- 

 magnets, the armature of which delivers a blow upon 

 the bead of dental plugging mallets used to impact 

 gold foil in prepared cavities of teeth. 

 Plumbagin [plum-baf-in). A peculiar crystallizable 

 principle found in Plumbago europmm, L., P. rosea, 

 L., and P., zcylanica, I.. 

 Plumbago { plum-ba'-gc) [plumbum, lead]. A genus 

 of the Plumbagineo', lead wort. P. europaea, L. , is 

 indigenous to Europe. The root (radix dentariae) and 

 acrid juice are vesicant. It is used in toothache, as 

 an application in skin-diseases, and internally as an 

 emetic. It contains ophioxylon and plumbagin. P. 

 zeylanica, L., chitrak, chita, of the old- word tropics. 

 The poisonous root is used in China as a sudorific, 

 sialagog, antiperiodic, and vesicant under the name of 

 yen-lai-hung. 

 Plumbite (plum'-bit^. A general term for any com- 

 pound formed by union of lead oxid with a base. 

 Plumula. (See Illus. Diet. 2. Arnold's name for 

 minute transverse furrows on the roof of the aqueduct 

 of Sylvius. 

 Pluricordonal ( ' plu-re-kord' -on-al) [plus, more; 



chorda, a string]. Having several processes. 

 Plurifetation ( pln-re-fe-ta'-saun) [ plus, more; fatus, 

 fetus]. The conception of twins, triplets, etc. 



