ARACHXODEITIS 



89 



ARCH 



inodeitis, Arachnoditis {ar-ak-no-di'-tis). See 

 - Illus. Diet.'). 

 ; ichnodermous (ar-ak-no-dur'-mus) [dpdx^n, a 

 s web; 6ip/ia, the skin]. Having a very thin 



iachnoid. (See lllus. Diet.) 2. The arachnoid 



lembrane. Syn., Me mbr ana media cerebri ; Menin- 



: Meningium : Meninx arachnoidea : Meninx 



: : Meninx serosa. 3. Pertaining to a membrane. 



Thready, feeble, araneous ; said of the pulse. 



I ichnoideitis \ar-ak-noi-di f -/is). See Arachnitis 



Lllus. Diet ). 

 t ichnoitis {(ir-ak-no-i'-tis). See Arachnitis (Illus. 



/ ichnology \ar-ak-nol'-o~je) [apdxvrj, a spider; 

 . science]. The study or science of spiders, 

 yn.. 

 I xhnolysin ar-ak-nol'-is-in) [dpd\vr/, a spider ; 

 - . a loosing]. A very active hemolytic sub- 

 ance extracted from spiders. It is destroyed by- 

 eating to 70 or 72°0., and is probably identical 

 ith Robert's toxalbumin of spiders. 

 t ichnophilous {ar-ak-nof'-il'-us) [dpd\r'j, a spider; 

 1 , to love]. Applied to fungi growing upon dead 

 aiders. 

 / ilietin (ar-al-i'-el-in). See Araliretin. 

 P .liin [ar-aS-le-in). A glucosid found by v. Holden 

 e bark of Aralia spinosa. A white crystalline 

 ■luble in water and alcohol, insoluble in 

 her, benzol, and chloroform. 

 / liretin (ar-al-ir'-e-/in). A decomposition-product 

 araliin. 



a picacaballo. Horse-biter, a poisonous species 

 ■ale or bird spider found in Central America. 

 f'meiform (ar-an-e / -i-form) [aranea, a spider ; for- 

 rm]. Shaped like a spider. 



-an'-e-in) [aranea, a spider]. A liquid 



ned from the punctured abdomen of spiders. It 



as an embrocation in homeopathic practice. 



soid ar-an'-e-oid) [aranea, a spider ; eldoc, like- 



Spider-like. 



Aneology (ar-an-e-ol'-o-je) [aranea, a spider; /.6-^oc, 



ience]. See Arachnology. 

 P neous. (See Illus. Diet.) 2. Applied to a thready, 



eble pulse. 3. Consisting of separate filaments. 

 P rabin (ar-ar^-ab-in). See Arabin (Illus. Diet.). 

 P. tacio. The South American name for Sagotia ra- 

 . Baill., a euphorbiaceous plant used as a tonic 

 J id aphrodisiac. 



P ucaria [a r- aw- ha' -re -ah) [Arauco, a province in 



A ijenus of plants of the order Coniferce. 



braziliana, A. Rich., yields part of the gum 



tmmar : v. ; of commerce. 



P acin ar'-bas-in) [Arbacia, Gray, a genus of the 



idnc (arbacia, similar)]. A histon-like body 



, >tained from spermatozoa of the sea-urchin, Arbacia 



'a/a, Blains. 

 P oricolous (ar-bor-ik'-ol-ns) [arbor, a tree ; colere, 



)it]. Growing upon or living in trees. 

 A orization. (See Illus. Diet.) A., Terminal, I. 

 I branched end of a sensory nerve. 2. A motor end- 

 i ate. A., Vascular, a tree-like branching of blood- 

 | ssels. 

 A utose ar'-bn-toz). A crystalline substance con- 

 ning glucose. 35 ' r : arbutin, 55', ; and water. io' r . 

 lined in the extraction of arbutin from Arc/o- 

 ttva ursi. 

 A (See Illus. Diet.) 2. A segment of a circle. 

 ■1 Bigonial 1 of lower jaw i, a measurement around 

 >r margin of the jaw. A., Diastaltic Ner- 

 >us, Marshall Hall's term for the nerves concerned 

 a reflex action. A., Frontal, the measurement 



from the nasion to the bregma. A., Maximum 

 Transverse, the measurement across the face from 

 points just anterior to the external auditory meati. A., 

 Nasomalar, measurement between the outer margins 

 of the orbits over the nasion. A.. Occipital, measure- 

 ment from the lambda to the opisthion. A., Parietal, 

 measurement from the bregma to the lambda. A.. 

 Voltaic, the band of light formed by the passage of a 

 strong electric current between two adjacent carbon 

 points. 



Arcade (ar-kdd / ) [arcus, an arch]. 1. A series of 

 arches ; an arch. 2. The bow of a pair of spectacles. 

 A., Crural, Poupart's ligament. A., Flint's, the 

 arteriovenous arch about the base of the renal pyra- 

 mids. A., Temporal, A., Temporal, Inferior, the 

 zygoma. A., Temporal, Superior, the orbital arch. 



Arcatura (ar-ka-tu'-rah) [anus, a bow]. A condi- 

 tion of horses marked by the undue outward curvature 

 of the forelegs. 



Arcein 1 ar'-se-in). Arecolin hydrobromate ; it is an 

 active myotic. 



Arch. (See Illus. Diet.) 2. A part of a circle. A., 

 Abdominothoracic, the lower boundary of the front 

 of the thorax. A., Alveolar, that marking the out- 

 lines of the alveolar processes of the jaw. A., Anas- 

 tomotic, one uniting two veins or arteries. A., Ante- 

 rior (of the arm), a plexus anterior to and above the 

 elbow, formed by a division of the anastomotic artery of 

 the arm and divisions of the ulnar and radial recurrent 

 arteries. A., Anterior hyoid, a general term which 

 includes the tympanohyal, epihyal, stylohyal, and 

 ceratohyal arches. A.s, Aortic, a series of pairs of 

 vascular arches situated in the branchial arches of the 

 vertebrate embryo and the adult Branchiahr, uniting 

 the cardiac and dorsal aortas. They are five in the 

 human embryo, the first and second pairs of which 

 disappear at an early stage ; the carotid arteries are 

 formed from the third pair, the arch of the aorta and 

 the subclavian arteries from the fourth pair ; the fifth 

 disappears on the right side, but on the left forms the 

 pulmonary artery, the ductus arteriosus, and the aorta. 

 A. of the Atlas, Anterior, that part of the atlas lying 

 ventrad to its articular surfaces. A. of the Atlas, 

 Posterior, the part of the atlas lying dorsad to its ar- 

 ticular surfaces. A.s, Axillary, twigs of the latis- 

 simus dorsi sometimes passing over the vessels and 

 nerves to the anterior part of the axilla, where they 

 disappear in the tissues. A., Carpal, Anterior, a 

 network on the anterior aspect of the wrist, composed 

 of little tranches of the carpal divisions of the radial 

 nnd ulnar arteries A.. Carpal, Dorsal, one formed 

 on the dorsum of the wrist by the junction of the pos- 

 terior carpal branch of the radial artery and a similar 

 one of the ulnar. A.s, Cephalic. See A., Pos/oral 

 (Illus. Diet.). A.s, Cervical, the fourth and fifth 

 postoral arches. A. of the Colon, the transverse 

 colon. A., Cortical, that portion of the renal sub- 

 stance which stretches from one column to another and 

 surrounds the base of the pyramids. A., Costal, the 

 arch of the ribs. A., Cotylopubic, the pubic arch. 

 A., Cotylosacral, one formed by the sacrum and the 

 osseous structures extending to the coxofemoral joints. 

 Syn., Standing arch. A., Cricothyroid, a curved 

 artery extending across the cricothyroid ligament, 

 formed by the junction of a branch from each superior 

 thyroid artery. A., Crural, Deep. See A.. Femoral, 

 Deep. A., Cubital, the arched end of the anterior 

 carpal artery at the knee of many quadnipeds. A., 

 Dental, 1. The parabolic curve formed by the cutting- 

 edges and masticating surfaces of the teeth. 2. The 

 alveolar arch. A., Dorsal of the arm), a plexus 

 above and below the elbow on the dorsal aspect of the 





