zodgloea 
Bacteria sometimes form a jelly-like mass by the swell- 
ing up of their cell-membranes ; this is the looglaa stage. 
Bessey, Botany, p. 212. 
2. A massing together of micro-organisms 
which occurs in a certain stage of their devel- 
opment, the collection being surrounded by a 
gelatinoid envelop. 
Liquids in which any of these Schizomycetes are active- 
ly developing themselves usually bear on their surface a 
gelatinous scum, which is termed by Prof. Cohu the Zoo- 
glcea. W. B. Carpenter, Micros., § sas. 
ZoSgloeic (z6-o-gle'ik), a. [< zooglcea + -Jc] Of 
the nature of' zooglcea ; pertaining to zooglcea. 
ZOOgloeoid (z6-o-gle'oid), rt. [< zooglcea + -oid.^ 
In bat., resembling, characteristic of, or belong- 
ing to the zooglcea stage or condition of a micro- 
organism. 
zoogonidium (z6'o-g6-nid'i-um), 11.; pi. zoogo- 
nidia (-a). [NL.,' < Gr. fijjoi', animal, + NL. 
gmiidium.J In bat., a locomotive gonidiiun; a 
gonidium provided with cilia, and hence capa- 
ble of locomotion. 
Each zoogonidium breaks itself up into sixteen new zoli- 
gonidia, forming sixteen small and new colonies. 
Besgey, Botany, p. 221. 
ZOOgonOUS (zo-og'o-uus), a. [< Gr. ^uoyovog, 
))roducing animals, < Cv"") animal, -I- -yovof, pro- 
ducing: see -goiwus.~\ S&me a,a viviparous. 
ZOOgony (zo-og'o-ni), n. [< Gr. i;<^oyovia, pro- 
duction of animals, < C^Jov, animal, -I- -}ovia, 
production : see -gony.'] Same as zoogcny. 
ZOOgraft (zo'o-graft), n. [< Gr. fifwi', animal, 
-t- E. graft.'] In surg., a piece of living tissue 
taken from one of the lower animals to supply 
a defect in the human body by grafting it on 
the latter. Also zooplastic graft. 
ZOOgrapher (zo-og'ra-fer), n. [< zoograph-y + 
-ec] A zoographist. 
ZOOgraphiC (zo-o-graf'ik), a. [< zoograph-y + 
-(■<?.] Descriptive of animals; pertaining to 
zoography. 
ZOOgrapIlical (z6-o-graf'i-kal), a. [< zoographic 
+ -al.] Same as zoographic. 
zoographist (zo-og'ra-fist), n. [< zoograph-y + 
-int.'] One who describes or depicts animals; a 
descriptive zoologist. 
zoography (zo-og'ra-fi), •». [< Gr. foov, animal. 
-f- -ypafia, (.'ypa(puv, write.] The description 
of or a treatise on animals; descriptive zool- 
ogy. 
ZoSgyroscope (zo-o-ji'ro-skop), n. [< Gr. fwof , 
animal, + E. gyroscope.'] An application of 
the principle of the zoetrope in which a series 
of pictures are placed in a rotating frame, and, 
as they pass between a lantern and a lens, are 
thrown in extremely rapid succession on a 
screen, so as to form a continuous but con- 
stantly changing picture. This device is used in 
the exhibition of continuous series of instantaneous pic- 
tures of animals in motion, etc. E. H. Knight, 
ZOOid (zo'oid), a. and n. [< Gr. (.(mziSk, like an 
animal, < C,^v, animal, + tWof, form.] I. a. 
Like an animal ; of the nature of animals ; hav- 
ing an animal character, form, aspect, or mode 
of existence, as an organism endowed with life 
and motion. See II. 
II. n. In biol., something like an animal ; 
that which is of the nature of an animal, yet is 
not an animal in an ordinary sense, and is not 
the whole of an animal in a strict sense ; one 
of the "persons" or recognizably distinct en- 
tities which compose a zoon ; that product of 
any organism, whether of animal, vegetable, or 
equivocal character, which is capable of spon- 
taneous movements, and hence may have an 
existence more or less apart from or indepen- 
dent of the parent organism. The biological con- 
ception of a zodid is a fundamental one, bordering upon an 
almost metaphysical detlnition of what may constitute in- 
dividual identity or non-identity in a given case : the term 
covers a multitude of cases which seem at first sight to 
have little in common, and its use in ordinai-y zoology and 
botany is consequently various. The general sense of the 
word is subject to tlie following specifications: (a) An 
ambiguous or equivocal organic body intermediate be- 
tween a plant and an animal, and not distinctly eitlier one 
or the other; a micro-organism or microbe not amenable 
to ordinai7 classiticatiou in natural liistory, as bacteria, 
bacilli, and micrococci; a protistan, as a moner; one of 
the lowest protozoans ; a protophyte. Such zooids are 
microscopic, and for the most part of extreme miimteness. 
See the distinctive names, and Monera, Primalia, Protix- 
txi. Protfyphyta. Protozoa, ih) One of certain peculiar cells 
of multicellular animals and plants which are endowed 
with special activities, have as it were an individuality of 
their own, and are capaide of a sort of separate existence. 
Zoijids of this class are mainly germinal or reproductive. 
The female geim (ovum) and the corresponding male ele- 
ment are respectively types of the whole. 'Ihey occur un- 
der many nioditlcations, which receive distinctive names; 
many of the smallest and simplest forms are indifferently 
known as sporefi. See sjxire-, fipf/re-/ormation. oospore, 
zoospore, sporozfioid, antherozoid, spermatozooid, and sper- 
7040 
zodlogy 
matozoon, with various cuts. The foregoing deflnitions zoologically (zo-6-loj'i-kal-i), af?l'. In the man- 
are independent of any distinction to be drawn between 
plants and animals ; the following are zoological, (c) Any 
animal organism which has acquired separate existence 
from anotlier by partition of that other into two or more 
ner oi a zoologist; on the principles or accord- 
ing to the doctrines of zoology; from a zoo- 
logical standpoint. 
intheprocessesoiflssion, gemmation, and the like. Such zoologist (zo-ol'o-jist), m. [< zoolog-y + -ist.] 
cases are numerous and diverse. Viewing the zoon or zoo- Otip whn i« vprspd in yonlnirv a hiolniriRt 
logical unit as the entire productof an impregnated ovum, ""<= ^ho IS versed in zoology , a DlOlogist. 
the parts or persons into which it maybe subsequently ZOOlOgy (zo-oro-Jl), li. 1= t .zoologie = iirt.zoolo- 
separated, without any true sexual generation, and conse- gia = Pg. It. zoologia = G. zoologie, (. NL. zoolo- 
quently without the origination of a .new zoon^ 5,?.??: gia, < Gr. ^^O", animal, + -/x>yia, < Atyew, speak : 
propriately termed zooids. The simplest case is when a 
zoon breaks into two or more pieces, and every piece pro- 
ceeds to grow the part which it laclis, and thus becomes 
wholly like the organism from which it was detached. 
Various annelids offer a case in point. Another and 
large class of cases is furnished by hydrozoans which suf- 
fer segmentation directly, or detach from tlreirmain stock 
various parts, as free medusoids and the like, these zooids 
serving to found new organisms. Allman defines the zobid 
of a hydrozoan as a more or less independent product of 
non-sexual reproduction. Proliferation or strobilation of 
parts which may become detached is also well illustrated 
in the proglottides or deutoscolices which form the joints 
of tapewomis ; tliese are zooids in so far as the parent 
worm is concerned, consisting of detachable genitals con- 
taining the elements of a new sexual generation. A sim- 
ilar multiplication by zooids without generation takes 
place among tunicates ; it is unknown of true vertebrates. 
One of the most interesting cases is afforded in the par- 
thenogenesis of some insects, as aphids, in which, by a 
sort of internal gemmation, swarms of zobidal aphids 
are budded in succession from one another to several re- 
moves from the original impregnation. The term zooid 
with some writers specifies all these ' ' inferior individuals " 
which thus intervene in alternation of generation between 
the products of proper sexual reproduction ; and such have 
been described as "the detached portions of an individ- 
ual in discontinuous development." (d) Any one of the 
recognizably distinct persons of a compound organism, 
whether actually detached or detachable or not ; any 
member of a colonial or social aggregate, as the polypites 
of a polypidom, the polypides of a polyzoary, and the like. 
Such zooids offer eveiy degree of separateness or separa- 
bility. In some cases they are extremely numerous, all 
alike, and inseparal)le from the common stock which they 
fabricate and inhabit, as tlie members of a coral or sea- 
mat. In other cases they are less numerous, and but 
slightly connected, and all alike, as the several members 
of a composite sea-anemone of the genus Zoanthug (see cut 
there). But the zooids of many hydrozoans, for instance, 
are quite different in both form and function, in the same 
individual, for the purpose of division of labor; and the 
zooids which tlms act as the different organs of one in- 
dividual are commonly distinguished by name, as gono- 
zooids, gaaterozooids, dactylozooids, spirozooids, etc. See the 
distinctive names. Also zoiinite (a mistaken use). 
zooidal (zo-oi'dal), a. [< zooid + -al.] Same 
as zooid. 
ZOOks (zuks), interj. A minced oath: same as 
gadzools. [Obsolete or (rarely) archaic] 
Zooks ! see how brave they march. 
Sheridan (?), The Camp, i. 2. 
Zooks ! are we pilchards, that they sweep the streets, 
And count fair prize what comes into their net? 
Browning, Fra Lippo Lippi. 
ZOOl. An abbreviation of zoology. 
ZOOlater (zo-ol'a-ter), ». [< zoSlatry, after idola- 
ter.] One who worships animals or practises 
zoiilatry. 
ZOOlatria (z6-o-la'tri-a), 11. [NL.] Same as zoiil- 
atry. 
The system of zoolatria, or animal worship, was said to 
have been introduced into Egypt by King Kekau of the 
Ilnd dynasty. W. R. Cooper, Archaic Diet., p. 67. 
ZOOlatrOUS (zo-ol'a-trus), a. [< zoolatr-y + 
-oils.] Worshiping animals; practising zool- 
atry ; of or relating to zoolatry. 
ZOolatry (zo-ol'a-tri), «. [< NL. zoolatria, < Gr. 
fvoj;, animal, -t- larpda, worship.] The worship 
of particular animals, as in the religion of the 
ancient Egyptians and of many other primitive 
peoples, either as representatives of deities, or 
on account of some fancied qualities or rela- 
tions. 
ZOOlite (zo'o-lit), «. [< Gr. fuov, animal, -1- 
'/.H)og, stone (see -lite).] A fossil animal; an 
animal substance petrified. Also zoolith. 
ZOOlith (zo'o-lith), H. Same as zoolite. 
Zo61ithic(zo-o-lith'ik),o. l< zoolith + -ic] Same 
as zoiilitic. 
ZOOlitic (zo-o-lit'ik), a. [< zoolite + -ic] Hav- 
ing the character of a zoolite ; relating to zeo- 
lites. Also zoolithic. 
ZOologer (zo-ol'o-ier), ». [< zodlog-y + -er.] 
A zoologist. [l^Iow rare.] 
zoologie (z6-o-loj'ik), a. [< zoology + -ic] 
Same as zoiilogical. 
zoological (z6-o-loj'i-kal), a. [< coiilngic + -nl.] 
Of or pertaining to zoology — Zoological garden, 
a park or other large inclosure in which live animals are 
kept lor public exhibition.— Zoological province, re- 
gion, etc., in zongeog., one of the faunal areas, varying in 
extent, into wliich the land-surface of the globe is natur- 
ally divisible with reference to the geographical distri- 
bution of animals. (See province, 6, region, 7, and zooge- 
ography.) CoiTcsponding divisions of the waters of the 
globe may take the same name when their surface-extent 
is considered, or are distinctively named (see Arctalia. 
etc.). Zoological areas regarded vertically, or as to depth 
of water, are often called zonesor belts. See zone, «., 4. 
see -ology.] 1 . The science of animals ; the nat- 
ural history of the animal kingdom ; the body 
of fact and doctrine derived from the scien- 
tific study of that series of organisms whose 
highest term is man : correlated with phytolngy 
(or botany) as one of the two main branches 
of biology. The connotation which the term has ac- 
quired during the last fifty years is very extensive, as a 
result of the application to zoological science of the most 
general laws and principles of biology. So far is zoology 
freed from the fonner restriction of its scope to the mere 
formalities of description, classification, and nomenclature 
(which constitute only systematic zoology) that it now in- 
cludes the results of all the biological sciences in so far 
as these are applicable to the study of animal structure 
and function. Such are phytogeny, or the origination of 
species, genera, etc. ; ontogeny, or the origination of the in- 
dividual animal ; embryology, or the prenatal life-history 
of organisms; paleontology or paleozoiHogy, the history 
of animals in geologic time; zoogeography, the history 
of animals as to their spatial relations ; zootomy or zoo- 
physics, tlie comparative anatomy of animals ; zoodynam- 
ics or biodynamics, animal physiology ; zoochemistry, the 
ciiemistryof animal substances and tissues ; zoopsychology, 
the science of animal instincts ; zootechnics, bionomics, or 
thremmatology, which regards the relations of living ani- 
mals to man ; and various other cognate branches of the 
general science. The name zoology is an old one, and 
some of its branches have been cultivated from antiquity. 
One of the earliest classifications of animals in which 
a modern zoological group can be clearly recognized is 
that ascribed to Moses, which was based primarily upon 
certain hygienic and sacerdotal considerations : for the 
"clean" beasts that "cleave the hoof" are ruminante ; 
certain " unclean " birds are carrion-feeding birds of prey, 
as the vulture ; and the non-ruminant artiodactyls (swine) 
ai-e characterized with special emphasis. The germ of 
modem zoology, as of other sciences, is commonly as- 
cribed to Aristotle. Though he tabulated no scheme, his 
three treatises on zoological subjects include a classifi- 
cation which shows great discernment. He divided the 
animal kingdom into two main branches : (1) 'i,va.t.p.a, 
Enirma, or 'blooded' animals, in the four classes of 
mammals, l>ird8, reptiles, and fishes — the Vertebrata, and 
nearly as they stand to-day ; (2) 'Acoi/io, Jnsema, or 
' bloodless ' animals, exactly the Invertebrata, of which he 
had four classes, his MaAdKia being cephalopods; MaAa- 
icoaTpaito, crustaceans;'Et'To>ia, insects (other arthropods 
than crustaceans); and *0<rTpa*to6ep^iaTa, univalve and 
bivalve mollusks (together with sea-urchins). Pliny the 
naturalist was an industrious and indiscriminate com- 
piler ; and no name of special note in zoology appears 
again until the middle of the sixteenth century, when 
the almost simultaneous works of three authors secure- 
ly founded the science and greatly enlarged its scope. 
Wotton (1552) followed Aristotle, but added to the system 
the Zoophyta (which long afterward became the Vermes 
of Linmeus and the Itadiata of Cuvier, and continue 
to be the "zoophytes" of the present day); Gesner and 
I3elon published treatises in 1555 ; and in 1.560 was started 
at Naples a society which had zoology among its objects, 
the Academia Secretorum Natuiie, suppressed by the 
church. The period between Gesner and Linnseus is some- 
times styled the " heroic age " of zoology. The advance 
upon Gesner was comparatively unmarked for a hundred 
years from his death in 1565 ; but the latter half of the 
seventeenth century witnessed great progress. The col- 
lection of animals from distant parts of the world in- 
creased ; such anatomical examinations as had been prac- 
ticable and had long been practised without the aid of the 
microscope were carried on with that instrument; and 
several still-existing societies were founded — the Aca- 
demia Natura; C'uriosorum (in 1651), the Eoyal Society 
(chartered in 1662), and soon afterward the Paris Academy, 
under Louis XIV. The immediate predecessor of Lin- 
nseus in this period was John Bay (1628-1705), who fixed 
the word species in the sense it was to bear from his 
day to Darwin, and did more than any other person to 
make the "Syatcma Naturte"of the Swedish naturalist 
possible. This work passed through twelve editions 
(17,16-68) in the lifetime of its author ; the present bino- 
mial system of nontenclature was first applied consistently 
to zoology in the tenth edition (1758). Linnsens also gave 
fixity to certain graded groups above the species— namely, 
the genus, order, and class of the " Regnum Animale "— and 
he recognized the variety below the species. The classes 
in 1766 were six: JIfammnfia, with 7 orders; jl cm, 6 orders; 
Amphibia, 3 ordei-s ; Pisces, 4 orders; Insecta, 7 orders; 
Vermes, 5 orders. The Linnean diagnoses were always 
crisp and sententious, if not always correct; and, faulty 
or inadequate as any of them may now appear to be, the 
practical convenience of this machinery of classification 
and nomenclature is inestimable. Though the notion 
of the fixity of species and other groups as special crea- 
tions, to which this system gave rise, is now known to be 
radically fallacious, the Linnean classification acquired 
almost the character of dogma, such as had many, cen- 
turies before attached to the writings of Aristotle and to 
the Mosaic traditions. This system may be said to have 
culminated with the close of the eighteenth century; 
and the early years of the nineteenth wrought impor- 
tant changes, both in form and substance, notably at the 
hands of Lamarck and Cuvier. Lamarok was the pivot 
upon which zoology turned from Linnseus to Darwin. His 
"Zoological Philosophy" of 1609 is separated by a half- 
century to a year from the "Systema Natui-se " of 17,'>8, 
and by exactly a half-century from Darwin's " Origin of 
Species," which was first published in November, 1859. 
Lamarckianism brought up the whole subject of modem 
