hewgag 
inch in diameter, with a hole near one end and 
closed with parchment at the other, producing, 
when blown, a loud doleful sound. It was 
in use about 1856. Hence 2. An imaginary 
musical instrument feigned to be loudly sound- 
ed on occasions of special jubilation. [Humor- 
ous, U. S.] 
To-day Hanscomh sends a letter "all about it " [Dawes's 
flrst speech in Congress], setting it out with the accom- 
panying "sound of hem-gag." 
S. Bowles, In Merriam's Bowles, I. 295. 
hewhole (hu'hol), n. [E. dial., regarded as hew 1 , 
r. , + obj. hole 1 , iu ref . to its wood-pecking habit ; 
also kighhole and highholder (in U. S.) ; formerly 
huhole (Florio), liewel (Marvell); in ME. hygh- 
whele (Halliwell), i.e. ' high-wheel 'j all these 
forms being various twists given m popular 
speech to the name otherwise presented in hick- 
wall, It ickway, q. v. ] The green woodpecker, Ge- 
C'IHUS viridi-s. [Prov. Eng.] 
hewn (him). A past participle of hew 1 . 
hexa-. [L. hexa-, repr. Gr. if, in comp. usually 
ffa-, in inscriptions also ff-, CK-, = L. sex = E. 
six, q. v.] An element of Greek origin or for- 
mation, meaning ' six.' 
hexacapsular (hek-sa-kap'su-lar), a. [< Gr. If, 
= E. six, + E. capsule + -ar.~\ In hot., having 
six capsules or seed-vessels: as, a hexacapsular 
plant. 
hexace (hek'sa-se), n. [< Gr. ff, = E. six, + axil, 
a point.] A summit of a polyhedron formed by 
the concurrence of six faces. 
Hexachaetse (hek-sa-ke'te), n. pi. [NL., < Gr. 
tf, = E. six, + NL. chceta, q. v.] A division of 
the brachycerous Diptera, containing those two- 
winged flies which nave a proboscis composed 
of six pieces, as the family Tabanida; : contrast- 
ed with Tetrachtette and Dichcetce. 
hcxachsetous (hek-sa-ke'tus), a. [As Sexachce- 
t<B + -0s.] Pertaining to or having the charac- 
ters of the Hexachastas. 
hexaehord (hek'sa-kord), n. [< Gr. ef, =E. six, 
+ xpd'l, a string, cord, chord.] 1. In Gr. 
music: (a) A diatonic series of six tones, (ft) 
The interval of a major sixth, (e) An instru- 
ment with six strings. 2. In medieval music, 
a diatonic series of six tones, containing four 
whole steps and one half-step (between the 
third and fourth tones). The hexaehord was an at- 
tempt to improve on the ancient tetrachord as a unit of 
musical analysis. The entire series of recognized tones, 
from the second G below middle C to the second E above 
it, was distributed among seven hexachords, beginning on 
G//, C,, F,, G,, C, F, and G, respectively. Each hexaehord 
was perfect in itself, and similar to every other ; its tones 
were designated in order by the syllables ut, re, mi, fa, 
sol, and la. (See tolmizatwn.') Any given tone was desig- 
nated both by its letter name and by its syllable name in 
full ; middleC, for example, being known as Csol-fa-ut, etc. 
In actual singing the solmization and the singer's concep- 
tion of the tones passed from one hexaehord to another as 
far as necessary, the process of changing being called muta- 
tion. In contrapuntal writing the most perfect possible 
imitation was considered to be that which occurred be- 
tween analogous tones of two hexachords. The hexa- 
ehord system is doubtfully attributed to Guido d'Arezzo, 
in the eleventh century. It continued in use until, in the 
eighteenth century, the octave as a unit of analysis and 
the modern theory of key-relationship were recognized. 
hexachronous (hek-sak'ro-nus), a. [< Gr. tfd- 
xpovof, < f, = E. six, + x/>6voc, time.] In anc. 
pros., having a magnitude of six primary or 
fundamental times ; hexasemic. 
hexacolic (hek-sa-kol'ik), a. [< Gr. t!jdKaAo,< 
ef, = E. six, + KO/.OV, a member: see colon 1 ."] In 
anc. pros., consisting of six cola or series: as, 
a hexacolic period. 
Hexacoralla (hek"sa-ko-ral'a), n.pl. [NL., < 
Gr. tf , = E. six, + KopdMiov, coral. J One of the 
chief divisions of the Coralligena, in which the 
fundamental number of the intermesenteric 
chambers of the body-cavity, and likewise of the 
tentacles, is six; the hexamerous Coralligena, 
as distinguished from the Octocoralla, which 
are octomerous. The common Aetiniidce, or sea- 
anemones, are an example. 
hexacorallan (hek"sa-ko-ral'an), n. One of 
the Hexacoralla ; a hexamerous coral. 
hexacoralline (hek'sa-kor'a-lin), a. and n. [< 
Hexacoralla + -ine 1 .'] I. a. Pertaining to or 
having the characters of the Hexacoralla. 
II. H. One of the Hexacoralla; a hexacoral- 
lan. 
hexact (hek'sakt), a. Same as hexactinal. 
hexactinal (hek-sak'ti-nal), a. [< Gr. If, = E. 
six, + nK-ic (OKTIV-), a ray, 4- -aZ.] Having six 
rays, as a sponge-spicule. 
hexactinellid (hek-sak-ti-nel'id), a. and . I. 
a. Pertaining to or having the characters of 
the Hexactinellidfe. Also liexactinelline. 
II. n. One of the Hexactinellidce. 
2819 
Hexactinellida (hek-sak-ti-nel'i-da), n. pi. 
[NL., < Hcmctiiirlla + -idn."] In Von Lenden- 
feld's system of classification, an order of si- 
licious sponges, characterized by the triaxial 
and generally hexactinal spicules, in soft me- 
soglrea, the supporting skeleton being often 
strengthened with silicious cement. 
Hexactinellidae (hek-sak-ti-nel'i-de), n. pi. 
[NL., < Hexactinella (< Gr. f, = E. six, + auric; 
(OKTIV-), a ray, + L. dim. -ella) + -idas."] The 
glass-sponges rated as a family of silicious 
sponges. 
hexactinelline (hek-sak-ti-nel'in), a. Same as 
l/cxactinellid. 
Hexactiniae (hek-sak-tin'i-e), n. pi. [NL., < 
Gr. If, = E. six, + OKTif (CIKTIV-), a ray.] A group 
of Actiniaria with paired septa. The number of the 
pairs of septa is at least six, usually more, and in that case 
increasing in multiples of six. The mouth is fissure 
shaped, and the esophagus has two esophageal grooves 
and two esophageal lappets. 
hexad (hek'sad), n. [< LL. hexas (hexad-), < 
Gr. tf<2f (efrfi-), the number six, < rf = E. six.'] 
1. The sum of six units; the number six; also, 
a series of six numbers. 2. In chem., an ele- 
ment the atoms of which have six times the 
saturating power or equivalence of the hydro- 
gen atom, as sulphur in certain conditions. 
Also spelled hexade. 
hexadacty lism (hek - sa - dak ' ti - lizm ), n. [< 
hexadactyl(ous) + -ism.\ The condition of be- 
ing hexadactylous. 
hexadactylous (hek-sa-dak'ti-lus), a. [< Gr. 
ef, = E. six, + Sax.Tv'Aof, a finger.] Having six 
fingers or toes. 
hexade, n. See hexad. 
hexadic(hek-sad'ik), a. [< hexad + --ic.~\ Per- 
taining to six as a base of numeration. 
hexaedron (hek-sa-e'dron), n. See hexahe- 
dron. 
hexaemeron (hek-sa-em'e-ron), n. [LL. hexa- 
emeron, the six days of the creation, < LGr. 
ffooy/iepof , the six days' work (the title of a book 
by Basil on the six days of the creation), prop, 
adj., of or in six days, < Gr. If, = E. six, + 
rj/^spa, day.] 1. A term of six days. 2. A his- 
tory of the six days' work of creation, as con- 
tained in the first chapter of Genesis. 
The older account of the creation in Gen. ii. . . . does 
not recognize the hexaemeron, and it is even doubtful 
whether the original sketch of Gen. i. distributed crea- 
tion over six days. Encyc. Brit., XXI. 125. 
The first volume is occupied with the Mosaic Hexaeme- 
ron and the Deluge. Contemporary Rev., L. 752. 
hexafoil (hek'sa-foil), a. [< Gr. If, = E. six, + 
E. foil 1 , q. v.] Having six foils or lobes ; six- 
lobed. 
A vertical stem, rising from a wide Aza/b(-shaped base. 
5. K. Cat. Spec. Ex., 1862, No. 1018. 
hexagon (hek'sa-gon), n. [< L. hcxagonum, < Gr. 
it;dyui>ov, neut. of ffdyuwf, six-cornered, hexag- 
onal, < If, = E. six, + yiwia, a corner, angle.] 
In geom., a figure of six sides and six angles. 
If it be plane and the sides and angles are 
equal, it is a regular hexagon. 
hexagonal (hek-sag'o-nal), a. [< hexagon + -al.~\ 
1 . Having six sides and six angles ; having the 
form of a hexagon. The hexagonal system in crystal- 
lography includes such forms as the hexagonal prism, pyra- 
mid, etc., which are referred to three equal lateral axes in- 
clined at angles of 60 and a vertical axis of different length 
at right angles to them. (See crystallography.) Therhom- 
bohedral system is a division of the hexagonal in which the 
forms are referred, sometimes to three equal inclined axes 
parallel to the faces of the fundamental rhombohedron, 
but more commonly to the same axes as the hexagonal 
forms ; in the latter view the rhombohedron is regarded 
as the hemihedral form of a hexagonal pyramid, and simi- 
larly of the other forms. Hexagonal and rhombohedral 
forms have the same optical characters, both being uni- 
axial. 
2. Divided into hexagons: as, a surface with a 
hexagonal structure. 
hexagonally (hek-sag'o-nal-i), adv. In the 
form of a hexagon. 
hexagonienchymat (hek-sa-go-ni-eng'ki-ma), 
n. [NL.,< Gr. ffayuvor, six-cornered, hexagonal, 
+ iyx v /* a , an infusion: see enchymatous, and cf. 
parenchyma.] In T>ot., cellular tissue exhibit- 
ing hexagonal forms in section. 
hexagonous (hek-sag'o-nus), a. Same as hex- 
agonal. [Rare.] 
An hexagonoits plate embossed with angles. 
(mar. Jour. ofGeol. Soe., XLV. 172. 
hexagonyt (hek-sag'o-ni), u. [Directly < Gr. 
f, = E. six, + yavia, angle. Cf. hexagon."] A 
hexagon. 
When I read in St. Ambrose of hexagonies, or sexangn- 
lar cellars of bees, did I, therefore, conclude that they were 
mathematicians? Abp. Bramhall, Against Hobbes. 
hexakisoctahedron 
[< Gr. 
, of six 
Pascal's Hexagram. 
AB, BC, CD, DK, EF. FA are the 
successive lines ;^AB and DE intersect 
m /, KC and EF intersect in//. CD , u . . . 
andV.4 intersect in G; C. H, and / This 18 a hexagram in- 
are collinear. 
hexagram (hek'sa-gram), n. 
,uarof, of six letter's (cf. LGr. 
rms of weight), 
ef, = E. nix, 
+ ypdfi/ia, & line, 
letter, etc. : see 
</rat 2 .] l.Afigure 
formed of two equi- 
lateral triangles 
placed concentri- 
cally with their 
sides parallel and 
on opposite sides of 
the center. This 
was the seal or sym- 
bol of the Pytha- 
gorean school. 2. 
In geom., a figure of 
six lilies. The name 
Is particularly applied 
to the mystic hexagram 
invented by Pascal. 

exa 
scribed in a conic. It 
has the property that 
the Intersections of the first and fourth, the second and 
fifth, and the third and sixth lines lie on one straight 
line. This is a case of the elementary proposition that 
three cubic curves 
which have eight points 
in common also have a 
ninth in common. Bri- 
anchon's hexagram is 
circumscribed about a 
conic ; and the chief 
property of it is that 
the three lines joining 
opposite angles inter- 
sect in one point. 
3. In Chinese lit., 
one of the 64 fig- 
ures which form 
the basis of theYih- 
king or ''book of 
changes," one of 
the oldest Chinese 
books. Each of 
these figures is 
made up of six par- 
allel lines, of which some are whole and some 
divided. See took of changes, under change. 
Hexagrammidae (hek-sa-gram'i-de), n. pi. 
[NL., < Hexagrammus -f -idce.~\ A family of 
acanthopterygian fishes, represented by the 
genus Hexagrammus. It is characterized by enlarged 
suborbitals connected with the preoperculum, an elongated 
dorsal fln with its spinous and articulated portions sub- 
equal, an elongated anal fin, and perfect ventrals, each with 
a spine and five rays. The species are confined to the 
northern Pacific ocean, and are mostly found along the 
western coast of North America, especially California, 
where the typical species are improperly called rock-trout. 
The family is also called CJmidae, and by Giinther Hetero- 
lepidtz. 
HexagrammilS (hek-sa-gram'us), n. [NL., < 
Gr. ft;, = E. six, + ypa[i/ui, a line.] The typi- 
cal genus of Hcxagraminidai: so called from 
Brianchon's Hexagram. 
ABCDEI- is the hexagram. AD.BF.. 
and CF meet in one point, G. 
Steller's Rock-trout (Hfxagrammus asptr). 
the six more or less developed lateral lines, 
three on each side, of which one is median, one 
dorsal, and one abdominal. Steller's rock- 
trout, H. asper, is an example. 
hexagyn (hek'sa-jin), n. [< Gr. rf, = E. six, + 
-ywr/, female (in mod. bot. a pistil, style).] In 
the Linnean system, a plant having six styles. 
Hexagynia (hek-sa-jin'i-a), n.pl. [NL. : see 
hexagyn."] In the Liunean system, an order of 
plants, such as the sun-dew, having six styles. 
hexagynian (hek-sa-jin'i-an), a. [As lieiagyn 
+ -MM.] In bot., having six styles. 
hexagynous (hek-saj'i-nus), a. [As hexagyn 
+ -OMS.] Same as hexagynian. 
hexahedral (hek-sa-he'dral), a. [< hexahe- 
dr(on) + -aL] 1. Having ttie figure of a hexa- 
hedron; having six equal superficial sides or 
faces; cubic. 2. In entom., having six dis- 
tinct and more or less parallel sides ; six-sided : 
said of long bodies, as joints of the antennse, 
etc. 
hexahedron (hek-sa-he'dron), H. [< Gr. ef, = 
E. six, + edpa, seat, base, = E. settle 1 , n."\ A 
solid body having six faces; especially, the reg- 
ular hexahedron or cube. Also hexaedron. 
hexakisoctahedron (hek " sa - kis - ok - ta - he ' - 
dron), n. [< Gr. tf<k<f, six times (< ff = E. six), 
