LAMINA 



656 



LANCET 



pigment-cells between the retina and the choroid. 

 L., Posterior Elastic, the posterior layer of the 

 cornea ; the membrane of Descemet. L. prima 

 cutis, the epidermis. L. propria (of the tympanic 

 membrane), the middle or fibrous layer of the 

 tympanic membrane. L., Protovertebral, that por- 

 tion of the jnesoblast lying to the side of the chorda 

 dorsalis in which the protovertebrse subsequently form. 

 L. quadrigemina, a layer of gray matter, forming the 

 roof of the aqueduct of Sylvius. L. Quadrilateralis, 

 a term for the Clivus of Blumenbach, q. v. L., Reti- 

 cular, the hyaline membrane of the inner ear, extend- 

 ing between the conjoined head of Cord's rods and 

 Hensen's supporting cells. L. secundaria, one of 

 the secondary germ-layers, q. v. L. semicircularis. 

 See Tcenia semicircularis. L. sphenopetrosa, a small 

 plate of bone near the spinous foramen of the greater 

 wing of the sphenoid bone. L. spiralis, a thin plate 

 in the ear, osseous in the inner part and membranous in 

 the outer, which divides the spiral tube of the cochlea 

 into the scala tympani and the scala vestibuli. L. 

 spiralis ossea, a thin plate of bone that winds spirally 

 around the modiolus of the cochlea. L. supercho- 

 roidea, the delicate membrane of the outer surface of 

 the choroid tunic of the eye. L. tectoria. See 

 Lemniscus, Inferior. L., Terminal. I. See L. 

 cinerea. 2. The anterior terminal plate of the anterior 

 brain-vesicle. L. terminalis. See Terma. L. 

 triangularis (of the sphenoid bone), the posterior 

 triangular part of the great wing of the sphenoid bone. 

 L. transversa, one of the transverse laminae of the 

 cerebellum. L., Tympanic, the tympanic plate of 

 the petrous portion of the temporal bone. L., 

 Vascular, the endochorion. L. of Vertebra. See 

 Vertebra. L. ventralis, one of the lateral mesoblastic 

 plates. L. vitra, the inner or vitreous table of the skull. 

 L. visceralis, one of the thickened layers of meso- 

 blastic tissue on each side of the notochord, which by 

 proliferation and splitting form the splanchnopleure 

 and somatopleure. L., Vitreous (of the choroid), a 

 homogeneous membrane covering the inner surface of 

 the choroid ; it is also called the membrane of 

 Bruch. 



Laminae (lam' ' -in-e) [lamina, a thin plate]. The sensi- 

 tive plates of soft tissue, covering the entire anterior 

 surface of the coffin-bone in the horse. See also 

 Lamina. 



Laminage (lahm-in-ahzh') [Fr.]. Flattening; the 

 compression or flatwise crushing of the fetal head to 

 facilitate delivery. 



Laminal, Laminar (lam'-in-al, lam'-in-ar) [lamina, a 

 layer]. Composed of laminae ; having the form of a 

 lamina. L. Tissue, a synonym of Connective Tissue. 



Laminaria (lam-in- a' -re-afi) [lamina, a. thin plate]. I. 

 A genus of algae, or seaweeds. Several species are rich 

 in iodin. 2. The cured lower part of the stem of L. 

 cloustoni, or L. digitata. L. Bougie, a bougie made 

 of the stalk ; it is used for urethral dilatation. L. cor- 

 nica, L. digitata, devil' s-apron, tangle ; sea-tangle, 

 sea-girdles, or sea-wand ; cairn-tangle, dead-man's- 

 toe, oarweed. A species found in Scotland, very rich 

 in iodin ; the stem is used for the manufacture of tents 

 and bougies. L. esculenta, an edible species said 

 to have anti-scorbutic properties. L. Probe, a probe 

 made of the stalk, used to dilate the canaliculi and 

 nasal duct. L. saccharina, ribbon-weed ; sea-belt, 

 sweet-tangle, is rich in iodin and potash ; it is used 

 as food, and is also purgative. L. Tent, a tent 

 made of the stem of the plant, for dilatation of the 

 cervix uteri. 



Laminate, Laminated (lam'-in-dt, latn'-in-at-ed). See 

 Laminar. 



Lamination (lam-in-a' -shun) [lamina, a layer]. Ar- 

 rangement in plates or layers. An operation in 

 embryotomy, consisting in cutting the skull in slices. 



Laminectomy (la?n-in-ek f -to-me) [lamina, a layer; 

 EKTOfii], excision]. The operation of removing the 

 posterior vertebral arches. 



Lamineur (lam-in-ar') [lamina, a layer]. An instru- 

 ment for performing laminage, q. v. 



Laminitis (lam-in-i'-tis) [lamina, plate ; trig, inflam- 

 mation]. Inflammation of the laminae of a horse's 

 hoof; founder. 



Laminose (lam'-in-os) [lamina, a thin plate]. Thin, 

 membranous, or plate-like. 



Lamium (&'-«-««) [L. , the dead-nettle]. A genus 

 of labiate plants. L. album, the leaves and stems of 

 the plant L. album, with properties due to an alkaloid, 

 Lamin. It is useful in menorrhagia. Dose of the 

 tincture ^ss-ij. Unof. 



Lamnar (lam'-nar) [lamna, a thin plate]. A term 

 applied to nails that are flat, short and broad. 



Lamnectomy (lam-nek' -to-me). Same as Laminec- 

 tomy. 



Lamp [?Mf/.iTag, a lamp]. A vessel containing a liquid 

 capable of burning, and a wick. It is used to give 

 light. L., Aphlogistic, a lamp devised by Davy in 

 which glowing platinum furnishes the light. L. -black, 

 a fine black substance, almost pure carbon, made by 

 burning coal-oils in an atmosphere deficient in oxygen, 

 or by allowing a gas-flame to impinge on a cold surface. 

 See Pigments, Conspectus of. L., Laryngoscopic, a 

 small incandescent lamp used in laryngoscopy. One 

 form is provided with reflectors and lenses by 

 means of which light can be projected into the mouth, 

 pharynx, and larynx. L., Lee's, a lamp used in mer- 

 curial fumigation. L., Mercurial, a lamp consisting 

 of two cups, an upper for holding the mercury, a 

 lower for holding water. The latter is heated by 

 means of a Bunsen burner, the water and mercury 

 being both vaporized. L., Spirit, one in which 

 alcohol is used to produce heat rather than light. L., 

 Van Buren's, a device for mercurial fumigation. 



Lampas (lam' -pas) [Fr., lampas, lam pas]. A conges- 

 tive swelling of the fleshy lining of the roof of the 

 mouth, in the horse. 



Lampers (lam'-perz). See Lampas. 



Lamprophony (lam-proff f -o-ne) [Aafnrp6g sounding; 

 (puwrj, voice]. A sonorous, ringing quality of the voice, 



Lampsana (lamp-sa f -nah). See Lapsana. 



Lampsis (lamp' -sis) [?.d/iipig, a shining]. Splendor, 

 brilliancy. 



Lana (la'-nah) [L.]. Wool. 



Lanate (Ian' -at) [/i^voc, wool]. Woolly; lanuginousj 

 lanigerous; lanose. 



Lancaster Black-drop. Acetum opii ; vinegar of 

 opium. 



Lance (lans) [lancea, a lance or spear]. I. A lancet. 

 2. To open, as with a lancet or bistoury. L., Mau- 

 riceau's, a lance-shaped knife for opening the fetal 

 head in embryotomy. 



Lanceate (lan'-se-at) [lancea, a lance]. See /.. 

 late. 



Lanceolar (lan'-se-o-lar). See Lanceolate. 



Lanceolate (Ian' -se-o-lat) [lanceola, a little lance]. I 

 biology, shaped like a lance-head; thin and tapering 

 towards each end. 



Lancet (Ian' -set) [dim. of lancea, a lance]. A two 

 edged surgical instrument for incising tumors, etc. L.. 

 Gum, a small instrument in which the cutting portion 

 has a convex edge and is at right-angles to the shaft 

 L., Spring, one in which the blade is thrust out by 

 means of a spring, which is controlled by a trigger. 

 L., Thumb, one with a double-edged, broad blade. 



