PRUSSAK'S CHAMBER 



1198 



PSEUD ANTITROPY 



single symptom of itching, occurring either over the 

 entire cutaneous surface, or limited to certain regions. 

 The itching may be more or less constant, but is 

 likely to occur in paroxysms, and is usually worse at 

 night. It is not dependent upon any primary struc- 

 tural lesion of the skin, but excoriations and thicken- 

 ing result from the scratching. P. analis, P. ani, 

 itching around the anus. P. consensualis, eczema 

 the result of disturbances of internal organs. P. 

 flavescens. Synonym of Eczema impetiginosum. 

 P. hidroa. Synonym of Miliaria. P. hiemalis, 

 a form following exposure to cold, or existing only 

 in winter, especially in dry climates. P. localis, 

 pruritus limited to a part of the body. P. opii, 

 the itching that sometimes supervenes upon the 

 administration of opium. P. porcellanea. Synonym 

 of Urticaria. P. senilis, the pruritus of the aged, 

 often due to degenerative changes in the skin. P. 

 universalis, general itching of the surface of the 

 body. P. vulvae, itching around the vulva. This, it 

 should not be forgotten, is sometimes due to diabetes. 



Prussak's Chamber. Same as P. 's Space. P.'s Fibers, 

 two short, tightly-stretched striae extending from the 

 tip of the short process of the malleus to the notch of 

 Rivinus. P.'s Space, a small space lying above the 

 short process of the malleus, and bounded externally 

 by Shrapnell's membrane. 



Prussian (prush' -ati) [Prussia, Prussia]. Of, or per- 

 taining to, Prussia. P. Blue, the ferrocyanid of iron, 

 largely used in the arts as a dye and pigment ; it was 

 formerly used as a febrifuge, tonic, alterative, and anti- 

 epileptic. Dose gr. iij-y. Unof. See Pigments, 

 Conspectus of. P. Brown, P. Green. See Pigments, 

 Conspectus of. P. Red. Same as Venetian Red. 



Prussiate (prus' '-e-at) [Prussia, Prussia]. A salt of 

 prussic, or hydrocyanic acid. 



Prussic (prus'-ik) [Prussia, Prussia]. Pertaining to 

 Prussian blue. P. Acid. See Acid, Hydrocyanic. 



Prussine (prus'-in). Synonym of Cyanogen. 



Psalidium (sal-id / -e-um). Synonym of Psalis. 



Psalidoma (sal-id-o / -mah) [ tpaMdu/na, arch]. The 

 ental surface of the skull. 



Psalis (sa'-lis) [\paXiq, arch]. The fornix of the cere- 

 brum. 



Psalistoma (sal-is' '-to-mah) [ipaXtg, scissors ; gtS/m, 

 mouth]. In biology, the cutting margin of the man- 

 dible of an arthropod. (Bate.) 



Psalloid (sal'-oid) [tpaXAeiv, to play on a stringed in- 

 strument ; e/rfof, form]. Lyriform ; resembling the 

 lyra of the brain. 



Psaloid (sa'-loid) [ipahig, an arch; elfiog, like]. Re- 

 sembling an arch. 



Psalterial (sawl-te' '-re-al) [ijm?iT7/ptov , a psaltery]. Re- 

 sembling a psalterium. 



Psalterium (sawl-te' '-re-um) [ipafor/pLov, a psaltery : pi., 

 Psalteria~\. I. Synonym of the Lyra. 2. A group 

 of longitudinal fibers on the floor of the Sylvian aque- 

 duct. (Bergmann.) 3. In biology, the third com- 

 partment of the complicated stomach of the Pecora 

 or true ruminants. It is globular in form and its lining 

 membrane is raised into longitudinal folds or laminae, 

 arranged very much like the leaves of a book and 

 very close together. It is also called Manyplies. 



Psammism (sam / -izm) [i/kz/z/xoc, sand]. 1. The use of 

 the sand-bath ; ammism. 2. The passage of gravel in 

 the urine. 



Psammocarcinoma (sam-o-kar-sin-o' -mah) [rpau/iog, 

 sand; KapKivofia, carcinoma]. A carcinoma contain- 

 ing a calcareous deposit. 



Psammoma (sam-o'-mah) [ijia/i/ing , sand ; bpa, tumor]. 

 A meningeal tumor containing sand-like material. It 

 is classed among the sarcomata. 



Psammotherapy (sam - - ther'- ap - e) [xfja/ipog, sand ; 

 depaneia, treatment] . Ammotherapy ; the therapeutic 

 use of the sand-bath. 



Psammous (iaM'-w) [ipa/u/uog, sand]. Sandy; sabu- 

 lous. 



Psapharous (saf'-ar-us) [i/«z0«pdc]. Friable; gritty. 



Psathyrous (sath'-ir-us). Synonym of Psapharous. 



Pselaphesis (sel-af-e' -sis) [ipz/Xafi/cng, touch]. 1. The 

 act of groping with the fingers, seen in the low delir- 

 ium of fevers; carphology. 2. Tickling, or ticklish- 

 ness. 



Pselaphia (sel-a / -fe-ah) [ipr/TiCHpia, touch]. 1. Digital 

 examination or exploration. 2. The same as Psela- 

 phesis. 



Pselaphotheca (sel - af - o • the' - kah) [ipr)la<pav , to feel 

 about; Oijkti, a box, chest: pi., Pselaphotheca:']. Tn 

 biology, the case or covering of the rudimentary palpi 

 in many butterfly pupae. 



Psellism, Psellismus (sel'-izm, sel-iz' -mus) [r 

 fide]. 1. Stuttering or stammering. 2. Defect of 

 speech due to hare-lip, or to cleft palate. 



Pseud- (sild-). Same as Pseudo-. 



Pseudacetic Acid (siid-as-e'-tik). Synonym of Propi\ 

 onic Acid. 



Pseudaconin (su-dak' -o-nin) [ijjevch'/g , false ; d«i 

 aconite], C, 27 H 41 N0 9 . A decomposition-product of 

 pseudaconitin. 



Pseudaconitin ( su-dak-on' -it-in) [ipevfrqg, false ; 

 itov, aconite], C 36 H 49 N0 12 . An extremely poisonou.- 

 alkaloid from aconitum ferox. Unof. 



Pseudacousma (su - dak - ooz'- mah) [ipevd/'/g, false ; 

 anova/M, a thing heard]. False hearing; a path 

 condition in which sounds are heard altered in pitcl 

 and quality. 



Pseudacusis (su-dak-u' '-sis) [ipsvSf/g, false; aaovc;; 

 hear]. Synonym of Pseudacousma. 



Pseudaesthesia (su-des-lhe / -ze-ah). See Pseu< 

 sia. 



Pseudallosematic (su-dal-o-se-maf -ik) [rrcevdfic, false 

 aTiTuoq, some other; aij/ia, a sign, mark, token]. 1: 

 biology, the displaying of a sign belonging to or char 

 acteristic of another. Applied by Poulton to the mi 

 colors assumed by comparatively defenceless animals 

 by means of which they imitate foreign object 

 ciated with some well-defined and aggressive sp 

 Thus the leaf-carrying ants of South America ( 

 ma), are mimicked by an immature homopteroi 

 sect possessing a shape and color closely resem 

 the ant, together with the leaf carried by it. 

 Mimicry, Pseudaposematic, Pseudepisematic, P. 

 malic. 



Pseudambulacral (su-dam-bu-la' -kral) [ijiFvAi/c, false 

 ambulacrum, a walk]. In biology, simulating 

 bulacra. 



Pseudamnesia (su - dam - ne f - ze - ah) [i/;n 



a^vrjdia, forgetfulness]. I. Spurious amnesia; 

 condition resembling amnesia, but of a transient 

 acter. 2. An erroneous form of the word . 

 nesia, q. v. 



Pseudangeiosis (su-dan-Je-o / -sis) [i/'n'^'/c, false . 

 elov, vessel ; v6aog, disease]. The developm- 

 blood-vessels in adventitious tissue. 



Pseudankylosis (su-danh-il-o'-sis) [fewh'jr, fal^c 

 hjoig, ankylosis]. A false joint. 



Pseudantitropy (su-dan-tit'-ro-p?) [fevih'/r, false; <• " 

 against; TprKFiv, to turn]. In biology, Wilder's 

 for the apparently antitropic relation between par 

 which are opposed to each other, but lie upon tl' 

 same side of an ideal plane. An example ol 

 dinal pseudantitropy is furnished by correspond^ 

 maxillary and mandibular teeth ; of lata 

 titropy, by the mesa! and lateral canthi of ths eye. { 



