Ptilocercus 
genus of Tupiiiitl.-i- or elephant-shrews, contain- 
ing a single species, /'. Imn-i, of Borneo, having 
a long tail furnished with distichous hairs to- 
ward the end, like a pen or feather, whence 
the name; the pentails. 
Ptilogonatinse (til-o-gon-a-ti'ne), w. pi. [NL., 
< J'tilogunys (-gonat-) + -inte.] A subfamily of 
oscine passerine birds, typified by the genus 
Ptilogonys, referred to the conventional family 
Ampelida. The bill is slenderer than In AmpeKt, with 
naked nasal scale and slightly bristled rictus ; the tarsus 
Is scutellate anteriorly and sometimes also on the sides ; 
the wings are rounded, with ten primaries, of which the 
first Is spurious ; the tall Is variable, and the head crested. 
The few species are confined to western North America, 
Mexico, and Central America. Also Ptilogonydinx. 
Ptilogonys (ti-log'o-nis), . [NL. (Swainson, 
1824), also in the forms Ptiligonyg, I'tiliof/onyn, 
and Ptilioaonatiis ; < Gr. JTT/'&W, wing, -I- yaw 
(j-orar-), knee, joint. Cf. gonyn.] 1. The typi- 
cal genus of I'tilogonatinie or Ptilogonydinx. 
The type is P. einereiix of Mexico. 2f. Ex- 
tended to birds of the genus Myiadestex and 
others. 3. [/. c.] A bird of the genus Ptilogo- 
nys in any sense. Townsend's ptilogonys is 
Myiadestes townsendi. The black ptilogonys is 
Phaiiiopepla nitenn. See cut under fly-snap- 
per. 
ptilollte (til'o-lit), H. [< Gr. nrD.ov, wing, + 
/Jflof, stone.] A zeolitic mineral, occurring in 
white tufts or spongy masses of minute acicular 
crystals, found in cavities in augite-andesite in 
Jefferson county, Colorado. It Is a hydrous silicate 
of aluminium, calcium, and potassium, and is remarkable 
for Its high percentage of silica. 
Ptilonopinae (til*6-no-pi'ne), n. pi. [NL., < 
Ptilonopiis + -inie.'] A subfamily of Colittnbidx, 
named from the genus PMonapus. P. ./. Kelky, 
1833. See Treroninx. 
Ptilonopus (ti-lon'p-pus), H. [NL. (Swainson, 
1837), prop. Ptiloptts,\Gr. mihav, feather, + Troff 
=^ E. foot.] An extensive genus of pigeons of 
the family f'olumbidje, giving name to the Ptilo- 
nopinse. Also Ptilinopiix (Sieaiuson, 1825) and 
Ptilopiix (Strickland, 1841). 
Ptilopaedes (til-o-pe'dez), w. pi. [< Gr. irri'/ov, 
down, + ;ra<r (7ra5-), child.] In ornitli., in 
Sundevall's classification, a primary group of 
birds, embracing such as are clothed at birth 
with down (which sprouts not only from ptery- 
1, but also from parts of the skin which form 
apteria when the true plumage is acquired), 
and are generally able to run about and feed 
themselves when hatched: opposed to I'xilopa- 
deg : nearly equivalent to Prtecocex, but of more 
exact signification. Also called Itaxypeedes, 
Auto/ihtK/i. 
ptilopaedic (til-o-pe'dik), o. [< Ptilopxd-cx + 
-tc.] Of or pertaining to the Ptiloptetlts ; pra>- 
cocial : opposed to pxilopfedic. 
Ptilophyton (ti-lof'i-ton), . [NL. (Dawson, 
1878), <Gr. Trri'Mv, feather, + Qyrov, a plant.] 
A plant of very uncertain affinities, so called 
by Dawson and supposed by him to be aquatic, 
and more likely to have been allied torhizocarps 
thaii to any other group. It consisU of beautiful 
feathery fronds, bearing on parts of the main stem or 
petiole small rounded sporocarps. It is found In the De- 
vonian and Lower Carboniferous of New York, In Nova 
Heotla, and In Scotland. 
Ptilopteri (ti-lop'te-ri), n. pi. [NL., < Gr. jrri- 
fav, leather, + irrep&v, wing.] The penguins 
as an order of birds: conterminous with Im- 
peiineH, ttquamijtenneii, Uplienisci, and Sphenisco- 
morphse. 
Ptilorhis (til'o-ris), . [NL. (Swainson, 1825), 
erroneously Ptilornin and Pttlitri^, prop. *Pti- 
lorrhis, < Gr. vTi).ov. soft feather, + pic. (ptv-), 
nose.] A genus of Paradiseidee, belonging to 
the subfamily Epimacliina, or slender-billed 
birds of paradise, haying the tail not longer 
than the body, and a jugular shield of metallic 
plumes. The nostrils are feathered, whence the name. 
Four species of these beautiful birds Inhabit Australia and 
New Guinea P. paraduea, the rifle-bird, P. mcturix, I'. 
albrrti, and P. (Cnupediqihora) magniftca. See cut under 
rifle-bird. 
ptilosis (ti-16'sis), B. [NL., < Gr. irriZuoif, plu- 
mage, also a disease of the eyelids resulting in 
loss of the eyelashes, < JtriAoioftu, be winged 
(or feathered), < nTi/ov, feather, wing.] 1. In 
in mill., plumage; the feathering of a bird, con- 
sidered with reference to the texture or other 
character of the feathers themselves. Com- 
pare jttrryli<i*. %. In mcd., loss of the eye- 
lashes. 
Ptilota (ti-16't), n. pi. [NL. (Macleay, 1H21 ), 
< Gr. n-r//jjrof, winged, verbal adj. of Tniowr- 
Oai, be winged: see ittiloxix.] In Macleay's 
eUssiticntioM, one of the prime divisions of the 
4828 
class limn-In, distinguished from Aptera, cor- 
responding to Lativillr's riiTiiilii-rrn, and di- 
vided primarily into Aliindibiilata and Hnustel- 
Illtil. See I'll I'l/i/nlil. 
Ptilotis (ti-ld'tts), n. [NL. (Swainson, 1837), 
< Gr. TTTi/jtv, feather, + oi'c (UT-) = E. ear.} A 
very extensive genus of meliphagine birds. It 
includes nearly 40 species, ranging through the Anstro- 
malayan, Australian, and Polynesian regions, mostly of 
plain dull olivaceous and yellowish colors, with the skin 
of the sides of the head often bare and wattled, or the 
parotlc feathers (ear-coverU) stiffened and usually white 
or yellow, forming a conspicuous mark, whence the uame. 
P. chrysotig and /'. ntru/it-nlaltt are examples. 
Ptinidae (tin'i-de), w. /. [NL. (Leach, 1819), < 
Ptiiiim + -idie.] A large family of serricorn 
coleopterous insects, containing beetles of 
small size, having the antenna? with from nine 
to eleven joints, the head retractile, and the ely- 
tra entire. Both larva; and beetles feed mostly on dead 
animal and vegetable matter. The larvae eat drugs, even 
pepper and tobacco. Some 44 genera and 150 species are 
recognized In the United States. Lasioderma serricornc 
is known in the I'nited States as the cigarette -beetle, on 
account of the damage it does to cigarettes. Sitodrepa 
panicea is a wide-spread museum-pest, and is found in 
many drugs. Members of the genus Anobimn are known 
as death-iratchen. Many of the species are cosmopolitan. 
See cut under book-worm. 
Ptinus (trims), H. [NL. (Linnaeus, 1767), ir- 
reg. < Gr. </>6ivciv, dOittv, decay, waste, destroy: 
see ]>hthi#is.] A large and wide-spread genus 
of beetles, typical of the family Ptiiiiax, of 
which about 80 species are known, 6 inhabiting 
the United States. A number of them occur both In 
Europe and in North America. P. .fur is cosmopolitan 
and a well-known museum-pest. See cut under bavlc- 
tronn. 
ptisan (tiz'an), w. [Also ptixane, formerly pty- 
sane, tisun ;" = F. tisane = Pr. fauna, tipsana = 
Sp. Pg. It. tixana, < L. ptixnna, < Gr. irTiadvt/, 
peeled barley, also a drink made from it, < 
TTTiaaftv, peel, husk.] 1. A mild harmless drink, 
or one having a slight medicinal quality, as 
barley-water or herb-tea. 
For what auncient phisitlon is there that in his workes 
commendeth not ptyoane, whiche is none other than pure 
barley braied in a niorter and sodden in water? 
Sir T. Klyot, Castle of Ilealth, li. 21. 
2. Grape-juice allowed to drain on the slab, 
without pressure, li. /'. Burton, Arabian Nights, 
V. 158, note. 
P. T. 0. An abbreviation of Please turn over: 
a direction, usually at the foot of a page, to call 
attention to matter on the other side of the 
leaf. 
ptochocracy (to-kok'ra-si), w. [< Gr. irrux^, a 
beggar (< xTuaoeiv, crouch or cower from fear), 
+ -K/mTia, < KtmTciv, nile.] Government by beg- 
gars; the rule of paupers: the opposite of plu- 
tocracy. [Kare.] 
It [the opposition to the extension of the county fran- 
chise! alleges the risks we run from the old and the rich, 
the danger of a gerontocracy and a ploutocracy ; whereas, 
to make Its argument good, it should have shown the irn- 
minence of a ptochocracy. 
Qiadttoiu, Gleanings of Past Years, I. 182. 
ptochogony (to-kog'o-ni), w. [< Gr. irrujof, a 
beggar, + -yavia, generation : see -gony.] The 
production of beggars; pauperization. [Rare.] 
The whole plan of the Bishop of London Is a ptochogony 
a generation of heggara. 
Sydney SmiUt, To Archdeacon Singleton, lii. 
Ptolemaean (tol-e-me'an), a. [< L. PUilenweux, 
I'toli iiiiiiiin, of Ptolemy, < Ptolenueitf, < Gr. 
IIroXf//aiof. Ptolemy.] Same as Ptolemaic. Mar 
Miiller, Sci. of Lang., p. 27. 
Ptolemaic (tol-e-ma'ik), a. [< Gr. IIroX^<i6f, 
pertaining to Ptolemy, < nroA//aiof, Ptolemy: 
see def.] Of or pertaining to Ptolemy; (a) 
relating to one or all of the line of Ptolemies, 
rulers of Egypt from the end of the fourth to 
the first century B. c. ; (b) relating to the Alex- 
andrian geographer and astronomer Ptolemy 
(see below) Ptolemaic chart. See Bonne'i map. 
projection, under projection, Ptolemaic system, the 
structure of the heavens according to Ptolemy, an gyp- 
tian-Greek astronomer, whuse recorded observations ex- 
tend from 127 to 151 A. 1>. His " Treatise of Mathematics " 
(MtMutnt}4i>ntif} commonly called the "Almagest," Is 
mainly devoted to an Investigation of the movements 
of the heavenly bodlea. Ptolemy holds that the earth 
Is stationary, because there is no appearance of varia- 
tion In the persjiective of the fixed stars. He admits 
It would simplify astronomy to suppose It routed dally 
on its axis, but thinks that refuted by physical consldera 
tliniH, while, regarding the stars as devoid of weight, he 
sees no objection to Mippiming them to move with Im- 
mense velocity. Hut these two errors of deny ink' the mo- 
tion of the earth both In translation and in rotation were 
not Incompatible with a correct representation of the mo- 
tions of the planeta relatively to the earth. The figure 
shows bin theory of Mare, which wa exactly like that of 
.luplter and Saturn. He supposed that about a circular 
deferent, which was really nearly similar and slmil-ult 
placed to the trueorMt of the i>lan>-talxit thi-snn, movrd 
Ptolemaic Theory of Man. 
ptyalogogue 
an epicycle, which was really of nearly the same propor- 
tionate size as the earth's true orbit and parallel to It this 
epicycle carrying the . 
planet on its circum- 
ference. In the fig. 
urc. T is the earth; 
XDIYJ, the orbit, 
deferent, or eccentric 
of Mars ; C, the cen- 
ter of the orbit ; OH, 
tbeequant; E,lts cen- 
ter; AKPL, the epl- 
7 elf ; D, Its center; 
, Mills; I.I, the line 
of nodes of the orbit ; 
K I ., the line of nodes 
of the eccentric 
(which Is parallel to 
the ecliptic) upon 
the plane of the or- 
bit. Mars revolves 
upon the epicycle so 
as to move uniformly relatively to P, the perigee of the 
epicycle, which It reaches so as to be then In opposition 
to the mean sun. The center D of the epicycle moves 
about the orbit so as to describe In equal times equal 
angles about E, the center of the equant C, the center 
of the orl.lt, Insects the eccentricity ET. The essential 
errors In his representation were as follows. (1) He rep- 
resented the deferent by the circle, thus giving It a breadth 
too great This circle remained In an eccentric position, 
whence It was called the eccentric, as well as the de.ferenl 
and the orbit. (2) Instead of supposing the moving radius, 
I'D, to describe equal areas in equal times, he drew a line to 
I), the attachment of the epicycle with the deferent, from 
E, really corresponding to the empty focus of the ellipse, 
but called by htm the center of the eauant, and he supposed 
this line ED to turn with an equable motion so as to de- 
scribe equal angles in equal times. This made an olnerr- 
able error only in the case of Mars. It made a tolerable ap- 
proximation to the elliptic motion, which excited the ad- 
miration of Kepler, and it shows that Ptolemy aimed at 
something much better than a mere harmonic analysis of 
the motions of the planeta. (8) He not only madetheepl- 
cvcle circular, but he placed Its center upon the deferent, 
thus virtually neglecting the eccentricity as well as the 
i Hi pticit. \ of the earth's orbit in Its effects on the apparent 
places of the exterior planets. (4) He made the planet re- 
volve in its epicycle so as to describe In equal times equal 
arcs measured from the perigee of the epicycle, as If the 
earth's motion were affected by the eccentricity of the or- 
bit of the other planet. And (ft) he made the planet come 
to the perigee of Its epicycle when It was just opposite the 
mean place of the sun, Instead of the true place. Other 
still more serious falsities affected his theories of the infe- 
rior planets and of the moon. Yet, notwithstanding all 
these errors, Ptolemy's theory satisfied pretty closely, In 
the cases of all the planets except Mercury and the moon, 
such observations as could lie made in his time. In hlx 
phrase, It "saved appearances." The Itolemaic theory 
continued In vogue until Copernicus(in Ifi43)explalned the 
relations between the motions of the planets and that of 
the sun, and thus supplied a method for determining the 
relative magnitudes ofthe different planetary orbits. But 
the system of Copernicus did not in itself represent the 
phenomena any Iwtter than that of Ptolemy ; and It was 
not until the great work of Kepler on the motions of Mars, 
published in IfiOO, that the real truth was known. The 
Almagest remains, however, a model of scientific investi- 
gation, most admirable for the genius with which Itman- 
ages not only the astronomical problems attacked, but also 
those of pure mathematics. 
Ptolemaist (tol-e-ma'ist), n. [< Ptolema-ic + 
-i'*f.] A believer in the Ptolemaic system of 
astronomy. 
ptomaine,' ptomain (to'ma-in), w. [Irreg. < Gr. 
flruua, a corpse (prop, that which is fallen, < 
iriiTTtiv, fall), + -ine 2 .] A generic name of al- 
kaloid bodies formed from animal or vegetable 
tissues during putrefaction, and the similar 
bodies produced by pathogenic bacteria. Some 
of them are poisonous. 
ptosis (tp'sis), n. [< Gr. itruaif, a fall, a fall- 
ing, < ;r/iTTfiv(perf. svirrura, verbal adj. irrarof), 
fall, = L. petere, fall upon, attack, seek, etc.: 
see petition.] A falling of the upper eyelid, or 
inability to raise it, due to paralysis of the 
levator palpebra 1 . Slight ptosis may be due to pa- 
ralysis of Muller's muscle Innervated through the cervical 
sympathetic. Also called Ueptiarojttoni, bJepharoplegia. 
ptotic (to'tik), (i. [< ptoxix ( plot-) + -it.] Per- 
taining to, characterized by, or affected with 
ptosis. 
ptyalin, ptyaline (ti'a-1""), n. [< Gr. nnWov, 
spittle, < -nri'tiv, spit : see spete .] The peculiar 
principle of saliva, believed to be a proteid 
body, which acts as a ferment on starch, rapid- 
ly converting it into dextrose. 
ptyalism (ti'a-Hxm), >i. [< (Jr. nruoA/o/ioV, a 
spitting, < TTTiii/.ifriv, spit much: see ptyali:t-.\ 
In inni.. salivation; a morbid and copious ex- 
cretion of salivii. 
ptyalize (ti'a-liz), r. i. ; pret. and pp. /ilytilizi-d. 
ppr. ptetMtww, [< Gr. moUfwr, spit much. 
< -Tiri'/oi; spittle, < irrmv, spit: see ptyalin.\ 
To salivate. 
ptyalogogic (ti a-lo-goj'ik), . [<. ptynl,njog>te 
+ -/c.] Promoting n flow of salivu. 
ptyalogogue (ti-nlYi-gog), . [< Gr. m-rn/ov, 
Kpittle, + ",'','". leading, < i'i)nr. do. bring.] 
licinc which causes salivation, or flo 
of saliva. 
