FAUNA (Lat. _Fauni_, the rural deities of the Romans). The general a.s.semblage of the animals of any region or district.

FAVOSITES (Lat. _favus_, a honeycomb). A genus of Tabulate Corals.

FENESTELLIDae. (Lat. _fenestella_, a little window). The "Lace-corals," a group of Palaeozoic Polyzoans.

FILICES (Lat. _filix_, a fern). The order of Cryptogamic plants comprising the Ferns.

FILIFORM (Lat. _filum_, a thread; _forma_, shape). Thread-shaped.

FLORA (Lat. _Flora_, the G.o.ddess of flowers). The general a.s.semblage of the plants of any region or district.

FORAMINIFERA (Lat. _foramen_, an aperture; _fero_, I carry).

An order of Protozoa, usually characterised by the possession of a sh.e.l.l perforated by numerous pseudopodial apertures.

FRUGIVOROUS (Lat. _frux_, fruit; _voro_, I devour). Living upon fruits.

FUCOIDS (Lat. _fucus_, sea-weed; Gr. _eidos_, likeness). Fossils, often of an obscure nature, believed to be the remains of sea-weeds.

FUSULINA (Lat. _fusus_, a spindle). An extinct genus of _Foraminifera_.

GANOID (Gr, _ganos_, splendour, brightness). Applied to those scales or plates which are composed of an inferior layer of true bone covered by a superior layer of polished enamel.

GANOIDEI. An order of Fishes.

GASTEROPODA (Gr. _gaster_, stomach; _pous_, foot). The cla.s.s of the Mollusca comprising the ordinary Univalves, in which locomotion is usually effected by a muscular expansion of the under surface of the body (the "foot").

GLOBIGERINA (Lat. _globus_, a globe; _gero_, I carry). A genus of _Foraminifera_.

GLYPTODON (Gr. _glupho_, I engrave; _odous_, tooth). An extinct genus of Armadillos, so named in allusion to the fluted teeth.

GONIAt.i.tES (Gr. _gonia_, angle). A genus of Tetrabranchiate Cephalopods.

GRALLATORES (Lat. _gralloe_, stilts). The order of the long-legged Wading Birds.

GRAPTOLITIDae. (Gr. _grapho_, I write; _lithos_, stone). An extinct sub-cla.s.s of the _Hydrozoa_.

GYMNOSPERMS (Gr. _gumnos_, naked; _sperma_, seed). The Conifers and Cycads, in which the seed is not protected within a seed-vessel.

HALITHERIUM (Gr. _hals_, sea; _therion_, beast). An extinct genus of Sea-cows (_Sirenia_).

HAMITES (Lat. _hamus_, a hook). A genus of the _Ammonitidoe_.

HELIOPHYLLUM (Gr. _helios_, the sun; _phullon_, leaf). A genus of Rugose Corals.

h.e.l.lADOTHERIUM (Gr. _h.e.l.las_, Greece; _therion_, beast). An extinct genus of Ungulate Mammals.

HEMIPTERA (Gr. _hemi_, and _pteron_, wing). An order of Insects in which the anterior wings are sometimes "hemelytra."

HESPERORNIS (Gr. _Hesperos_, the evening star; _ornis_, bird).

An extinct genus of Birds.

HETEROCERCAL (Gr. _heteros_, diverse; _kerkos_, tail). Applied to the tail of Fishes when it is unsymmetrical, or composed of two unequal lobes.

HETEROPODA (Gr. _heteros_, diverse; _podes_, feet). An aberrant group of the Gasteropods, in which the foot is modified so as to form a swimming organ.

HIPPARION (Gr. _hipparion_, a little horse). An extinct genus of _Equidoe_.

HIPPOPOTAMUS (Gr. _hippos_, horse; _potamos_, river). A genus of Hoofed Quadrupeds--the "River-horses."

HIPPURITIDae. (Gr. _hippos_, horse; _oura_, tail). An extinct family of Bivalve Molluscs.

HOLOPTYCHIUS (Gr. _holos_, whole; _ptuce_, wrinkle). An extinct genus of Ganoid Fishes.

HOLOSTOMATA (Gr. _holos_, whole; _stoma_, mouth). A division of _Gasteropodous Molluscs_, in which the aperture of the sh.e.l.l is rounded, or "entire."

HOLOTHUROIDEA (Gr. _holothourion_, and _eidos_, form). An order of _Echinodermata_ comprising the Trepangs.

h.o.m.oCERCAL (Gr. _h.o.m.os_, same; _kerkol_, tail). Applied to the tail of Fishes when it is symmetrical, or composed of two equal lobes.

HYBODUNTS (Gr. _hubos_, curved; _odous_, tooth). A group of Fishes of which _Hybodus_ is the type-genus.

HYDROIDA (Gr. _hudra_; and _eidos_, form). The sub-cla.s.s of the _Hydrozoa_, which comprises the animals most nearly allied to the Hydra.

HYDROZOA (Gr. _hudra_; and _zoon_, animal). The cla.s.s of the _Coelenterata_ which comprises animals constructed after the type of the Hydra.

HYMENOPTERA (Gr. _humen_, a membrane; _pteron_, a wing). An order of Insects (comprising Bees, Ants, &c.) characterised by the possession of four membranous wings.

ICHTHYODORULITE (Gr. _ichthus_, fish; _dorus_, spear; _lithos_, stone). The fossil fin-spine of Fishes.

ICHTHYOPTERYGIA (Gr. _ichthus_; _pterux_, wing). An extinct order of Reptiles.

ICHTHYORNIS (Gr. _ichthus_, fish; _ornis_, bird). An extinct genus of Birds.

ICHTHYOSAURIA (Gr. _ichthus_; _saura_, lizard). Synonymous with _Ichthyopterygia_.

IGUANODON (_Iguana_, a living lizard; Gr. _odous_, tooth). A genus of Deinosaurian Reptiles.

INCISOR (Lat. _incido_, I cut). The cutting teeth fixed in the intermaxillary bones of the _Mammalia_, and the corresponding teeth in the lower jaw.

INEQUILATERAL. Having the two sides unequal, as in the case of the sh.e.l.ls of the ordinary bivalves (_Lamellibranchiata_). When applied to the sh.e.l.ls of the _Foraminifera_, it implies that the convolutions of the sh.e.l.l do not lie in the same plane, but are obliquely wound round an axis.

INEQUIVALVE. Composed of two unequal pieces or valves.

INOCERAMUS (Gr. _is_, a fibre; _keramos_, an earthen vessel).

An extinct genus of Bivalve Molluscs.