orthopterology 
-oloyy.] That branch of entomology which re- 
lates to Oi'tliii/i/i i'n. 
orthopteron (or-thop'te-ron), n. One of the 
Orllto/itrnt. [Kare. | 
orthopterous (or-lhop't<;-rii>t), a. [< NI,. nr 
lln>i>li-nix, < (!r. njilln-ri i>nr, having straight (up- 
right) wind's or feathers, < "/<"';. straight. + 
n--ti>i'n', wing, = K.ji'iiiln-r.] Straight- winged ; 
having wind's that lie straight when folded; 
specifically, of or pertaining to (lie ()rlln>iili i'n. 
Orthoptic (or-thop tik), a. [< <<r. ii/itlin; straight, 
+ TT</i(ii;, of .seeing: sec o/ilir.'] Kelating to 
orthogonal intersect ions of I angcnts. Orthoptic 
locus, the locus of points where two tangents to a curve 
out each other at right ftnglrs. 
orthopyramid (or-tho-pir'a-mid), n. [< Gr. 
/'"'".. straight, + mipa/ttc, pyramid.) ln.rry.itnl., 
a pyramid of a monoclinic crystal lying be- 
tween the zono of unit pyramids and the ortho- 
domes: it is strictly a heraipyramid, since the 
form includes only four planes. 
Orthorhapha (or-thor'a-fji), . [NL., < Gr. 
<V;, straight, + pafyi/, a seam.] A suborder 
of dipterous insects or true flies, including 
those forms which escape from pupa through a 
T-shaped orifice, or rarely through a transverse 
rent between the seventh and eighth abdominal 
rings: distinguished from Cyrlorhiifilnt. It in- 
cludes all the midges and gnats, the horse-flies, 
robber-flies, bee-tlies, and others. 
orthorhaphous (fir-thor'a-fus), a. Of or per- 
taining to the Orthorltdjilin. 
orthprhomhic (6r-th9-rom'bik), a. [< Gr. bp06f , 
straight, + /><J///iof, a rhomb.] 1. Rectangular 
and rhombic. 2. In crystal., noting the sys- 
tem of crystallography which is characterized 
by three unequal axes intersecting at right an- 
gles ; belonging to this system : as, sulphur is 
orthorlitnuhir. Also called trimetric. See crys- 
tallography. 
orthpscope (or' tho-skop), n. [< Gr. bp86s, 
straight, + aianrelv, view.] 1. An instrument 
for hpldingwater around the eye, so that the re- 
fraction of the cornea is eliminated and the iris 
can be examined. 2. In eraniom., an instru- 
ment for drawing projections of skulls. 
orthoscopic (6r-tho-skop'ik), a. [< Gr. bp86f, 
straight, correct, + aiumeiv, view, + -j'c.] 1 . See- 
ing correctly; having normal vision. 2. Con- 
structed so as to present surrounding objects 
correctly to the eye : as, an orthoscopic eyepiece 
or ocular. 3. Presented in its normal appear- 
ance to the eye : as, an orthoscopic image. En- 
cyc. Brit., XVI. 273 Orthoscopic lens. See leru. 
orthose (6r'thos), . [< Gr. o/itfoc, straight, -f- 
-osc.~\ Same as orthoclase. 
Orthosia (6r-th6'si-a), n. [NL. (Ochsenhei- 
mer, 1816), < Gr. op#or, straight.] A genus of 
noctuid moths, typical of the family Orthosiidte, 
containing numerous species, of wide distribu- 
tion in Europe, Asia, Australia, and North 
America. 
Orthosiidse (6r-tho-si'i-de), n. pi. [NL. (Gue- 
n6e, 1841, as Orthosidtv), < Ortlwsis + -ida.] A 
family of noctuid moths, typified by the genus 
Orthosia, as defined by Guene'e, having 19 gen- 
era, some of them important and wide-spread. 
The antenna; in the male are pubescent or ciliate, in the 
female with isolated cilia; the palpi are almost always 
slender ; the proboscis is short or medium ; the legs are 
moderate and rarely spined ; the abdomen is often de- 
pressed ; the wings are entire and more or less pointed at 
the apex, with two plain median spots, the reniforni one 
often tinged with blackish below ; the median vein of the 
lower wings is trifld ; and the upper wings in repose en* 
tirely cover the lower, and cross each other on the lower 
border. The larva; have IB legs ; they are cylindric and 
velvety, with a globose head, and no prominences or tu- 
bercles; they live on the leaves of trees and plants, and 
hide during the day. The pupa; are smooth and glisten- 
ing, and contained in underground loose ovoid cocoons of 
silk and earth. 
orthosilicate (or-tho-sil'i-kat), n. [< Gr. i>p66c, 
straight, + E. silicate.'] A salt of orthosilicic 
acid (HiSiO^). Zinc orthosilicate (Zn^SiOx or 
2ZnO.SiO 2 ) is the mineral willemite : it is often 
called a nitinilic/ili, since it has an oxygen ratio 
of 1 : 1 . 
orthpsilicic (or'tho-si-lis'ik), o. [< Gr. bpBos, 
straight (see ortho-), + E. silicic.'] A word used 
only in the following phrase Orthosilicic acid, 
H4SiOi, a hypothetical acid which has never been isolated 
and is known only in it * salts, the orthosilieates or unisili- 
cates, which occur as minerals. 
Orthospermeae (6r-tho-sper'me-e), n. pi. [NL. 
(Bentham and Hooter, 186o), < Gr. bp86(, 
straight, erect, + n^f/i/ia, seed.] A series of 
cucurbitaceous plants having the ovule usually 
erect or ascending, it embraces 2 tribes (the Abo- 
brea and Cyclantlierece), genera, and about 13S species. 
Echinocyrtu belongs to this series. 
orthospermous (dr-tho-spi'r'mus), n. [< Gr. 
. straight, + <nrlp/ia, seed.) In In,/., hav- 
ing the seed straight. 
Orthostade (or'tho-stad), . [< Gr. bpthnr 
alsoo/^ofrrrirfmr, < bp86( t straight, upright,-}- TTO- 
i^im . standing, standing upright : sec .thulium. \ 
111 tine. i-iistiniii , a long and ample tunic, with 
straight or vertical folds. 
orthostichous (or'tho-sti-kus), ';. [< orthtuti- 
I'lii/ + -IIH.I.\ In hut., exhibiting ortlmstichy ; 
straight -ranked. 
orthostichy (6r'tho-sti-ki), . [< Gr. 
straight, + arixm', a row or line.] In hot., a 
vertical rank; an arrangement of members at 
different heights OH an axis so that their me- 
dian planes coincide, as the vertical ranks of 
leaves on a stem. 
When the leaves are arranged alternately on an axis so 
that their median planes coincide, they form a straight 
row or orthosHehy. Kneyc. Brit., IV. 110. 
orthostyle (or'tho-stil), n. [< Gr. bpdof, straight, 
+ ari'/.of, pillar, column : see style 2 .] In arch., a 
straight range of columns, as one of the sides of 
a peristyle : also used attributively. [Rare.] 
orthosymmetric (6r'tho-si-met'rik), a. [< Gr. 
u/Mf, straight, right, + av/j/ifrpia, symmetry: 
nt't'.nywiiiftrii:] Having right symmetry. See 
xi/ in mi-try.- Orthosymmetric determinant, seede- 
MFBMMNK 
orthosymmetrical (or-tho-si-met'ri-kal), a. [< 
oi-tlm.il/ni mi trie + -at] Same as orthosymmetric. 
Orthothecieae (6r'th6-the-si'e-e), n. pi. [NL., 
< (trthotlirrium + -co 1 .] 'A tribe of bryaceous 
mosses, taking its name from the genus Ortho- 
thecium. They arc generally large, widely spreading, 
and cespitose plants, forming wide yellow mats with erect 
or complanate branches, and smooth leaves with narrow- 
ly rhoinboidal or linear areolation which is large and quad- 
rate at the basal angles. The capsule is erect and sym- 
metrical, with double peristome. 
Orthothecium (or-tho-the'si-um), . [NL. 
(Schimper), < Gr. oflliuf, straight, -I- fty/.;/, a 
case: see thefa.~\ A small genus of mosses, 
typical of the tribe Orthotherieie, having eight- 
ranked close leaves, long-pedicellate, suberect, 
oval or oblong capsules, and double peristome, 
the teeth of which are narrowly lanceolate, 
yellowish, and distinctly articulate. There are 
three North American species. 
orthotomic (6r-tho-tom'ik), a. [As orthotom-ous 
+ -ic.] Cutting at right angles __ Orthotomic 
circle, a circle cutting three given circles at right angles. 
Orthotomic coordinates. See coordinate. 
orthotomous (or-thot'6-mus), a. [< Gr. bp86- 
ro/tof, divided evenly, ^ bpdoToficiv, cutting in a 
straight line, < bpfiof, straight, + rifivciv, rafulv, 
cut. ] Same as ortlioclastic. 
Orthotomus (or-thot'o-mus), n. [NL. : see or- 
thotomoiis.] A genus of grass-warblers or ma- 
lurine warblers founded by Horsfield in 1820 ; 
the tailor-birds. TherearelOorl2species,rangingover 
the Oriental region. The type of the genus la 0. sepiuin 
Tailor-hird of Java (Orthototnit 
of Java, Sumatra, and other islands. In the longest-known 
species, O. longirauda or O. ffutoria, the middle tail-feathers 
are long-cxserted. This form is often separated under 
the generic name Sutoria (which see). Also called Jiilrla. 
orthotone (or'tho-ton), o. and . [< Gr. bp06- 
TOVOS, having the proper accent, < 0/186$, straight, 
correct, + row>f, accent: see tone.'] I. . Ke- 
taining or acquiring an accent in certain posi- 
t ions or combinations, but unaccented in others : 
especially noting proclitics and enclitics when 
accented. 
orthros 
II. w. A word or form, usually enclitic or pro- 
clitic, when exceptionally reta'ining or acquir- 
ing an accent. Thus, the English articles, usually pi., 
I'lilic*, are orthotonts wln-n > nipliasizeil: an, I did not say 
a man, I saiil (/ in:>n. 
orthotone (or'tho-ton). r. I.; pri-t. and ]>p. <ir- 
lliiitiiiu ii, ppr. urtiiiitoiiiiti/. [< nrllintiiiii , n.] To 
accent (a word usually unaccented). 
orthotonesis (or tho-to-ne'sisi, . [NL., <Gr. 
^/'/./ror/,rr/i, the use of ttie full accent/ 'V""-i'/ 1, 
write with the proper accent, < o/i/A/rm, having 
the proper accent : sec in-lliniinii . \ Acci'ntua- 
tion, under certain conditions, of a word or form 
usually or in other combinations unaccented; 
especially, accentuation of a proclitic or an en- 
clitic: opposed to rurlixix. 
Thus the compound [Irish) verb ad I cobraim is ac- 
cented (in arthiitonuiu) adcobraim, whereas the game com- 
pound, used as a verbal noun (infinitive), takes the accent 
on ad. Amer. Jour. Pkilol., VI. 217. 
orthotonic (6r-tho-ton'ik), a. [< orthotone + 
-c.] Same as orthotone. 
In all other positions the verb is nrthntoniel. e. the ac- 
cent falls on the verb if there is only one prefix. 
Amer. Jour. I'kOul., VI. 218. 
orthotonus (6r-thot'o-nns), n. [NL.,< Gr. bpt)6f, 
straight, + reivttv, stretch (> rrfnof, tension).] 
Tonic spasm in which the body is held straight. 
orthotriaene (dr-tho-tri'en), . [< Gr. b/>H6{, 
straight, + rpiaiva,' a trident.] In the nomen- 
clature of sponge-spicules, a tria?ne whose three 
cladi or prongs project at right angles with the 
shaft; a simple spicule of the rhabdus type, 
trifurcate or with three secondary rays at one 
end, and these rays at right angles with the 
shaft. Solta#. 
Orthotricheae (6r-tho-trik'e-e), n. pi. [NL., < 
Orl/iiilrii-lium + -c<p.J A tribe of mosses, tak- 
ing its name from the genus Ortliotrirhutn , 
characterized by having tufted plants with 
leaves of close texture, a mitriform, often hairy 
calyptra, and a simple or double peristome, the 
outer row of eight bigeminate or sixteen gemi- 
nate, flat, short, entire or perforate teeth, the 
inner of eight or sixteen simple filiform cilia or 
lanceolate segments. 
Oi thotrichum (or-thofri-kum), n. [NL. (Hed- 
wig, 1801 ), so called in allusion to the hairs on 
the calyptra; < Gr. b/Mf, straight, + Opti- (rpix-), 
a hair. Cf . tfOerptXptit, have the hair stand on 
end.] A large genus of bryaceous mosses, 
typical of the tribe Orthotrithete. They are per- 
ennial plants, growing In tufts on trees or rocks, with usu- 
ally erect stems covered with crowded leaves, and a gen* 
'rally immersed capsule with peristome of sixteen teeth 
and calyptra usually covered with straight hairs, from 
which latter peculiarity they arc called brittle -mogges. 
There are nearly 40 North American species. 
orthotropal (6r-thot'ro-pal), a. [< ortholro- 
p-ous + -a/.] Orthotropo'us. 
orthotropic (6r-tho-trop'ik), a. [< orthotro- 
p-ous + -ic.] In lot., of or pertaining to or ex- 
hibiting orthotropism ; growing vertically. 
The primary shoot of the seedling [of Ivy] is, like that 
of Tropeeoluni, at first orthotrnjric and radial. 
Vine*, Physiology of Plants, p. 425. 
Orthotropism (6r-thot'ro-pizm), . [< orthot- 
rop-ous + -ism.'] In hot., vertical growth: a 
term proposed by Sachs for the habit of those 
organs of plants which grow more or less near- 
ly vertically, either upward or downward, as 
iris-leaves, the majority of physiologically ra- 
dial organs, etc. Compare plagtotropixm. 
Since the light is equally intense on all sides of the 
shoot, it exerts no directive influence. Orthotropum is 
then mainly due to negative geotroplsm. 
Eneye. Brit, XIX. 81. 
orthptropous (dr-thot'ro-pus), a. [< Gr. bp66f, 
straight, + rpeireiv, turn: see trope.] In hot., 
growing vertically or 
straight: applied specifi- 
cally to an ovule in which 
the chalaza is at the evi- 
dent base, and the orifice 
at the opposite extremi- 
ty, the whole ovule being 
straight and symmetrical. 
The ovules of the Polygonacrce, 
Urlicace<e, etc., are examples. 
Better atropal (which see). 
Also applied to an embryo in 
which the radicle is directed to 
the hilum or to the micropyle 
closetothehilum,astn ananat- 
ropous ovule. In the latter sense the same as homatropout. 
orthptypOUS (6r'tho-tl-pus), a. [< Gr. bpB6f, 
straight, + rrTor, form, type.] In mineral., 
having a perpendicular cleavage. 
orthros (or'thros), n. [< Gr. opOpof, dawn, morn- 
ing, eccl. office at dawn.] In the Gr. Ch., one 
of the canonical hours, corresponding to the 
Orthotropous Ovule. 
Flower of JuelaHs rttera, 
cut longitudinally and show- 
ing the ovule. 
