VI 



534 GLOSSARY 



Fungi (sing. Fungus') — A class of cellular plants, of which Mushrooms, 



Toadstools, and Moulds are familiar examples. 

 Furcula — The forked bone formed by the union of the collar-bones in many 



birds, such as the common Fowl. 



Gallinaceous Birds — An order of Birds of which the common Fowl, Turkey, 

 and Pheasant are well-known examples. 



Callus — The genus of birds which includes the common Fowl. 



Ganglion — A swelling or knot from which nerves are given off as from a 

 centre. 



Ganoid Fishes — Fishes covered with peculiar enamelled bony scales. Most 

 of them are extinct. 



Germinal Vesicle — A minute vesicle in the eggs of animals, from which the 

 development of the embryo proceeds. 



Glacial Period — A period of great cold and of enormous extension of ice 

 upon the surface of the earth. It is believed that glacial periods have 

 occurred repeatedly during the geological history of the earth, but 

 the term is generally applied to the close of the Tertiary epoch, when 

 nearly the whole of Europe was subjected to an arctic climate. 



Gland — -An organ which secretes or separates some peculiar product from 

 the blood or sap of animals or plants. 



Glottis — The opening of the windpipe into the oesophagus or gullet. 



Gneiss — A rock approaching granite in composition, but more or less lami- \'i 



nated, and really produced by the alteration of a sedimentary deposit 

 after its consolidation. ;; 



Grallat ores— The so-called Wading-birds (Storks, Cranes, Snipes, &c.), which 'i 



are generally furnished with long legs, bare of feathers above the 

 heel, and have no membranes between the toes. ( 



Granite — A rock consisting essentially of crystals of felspar and mica in a 

 mass of quartz. 



Habitat — The locality in which a plant or animal naturally lives. 



Hetniptera — An order or sub-order of Insects, characterized by the posses- 

 sion of a jointed beak or rostrum, and by having the fore-wings 

 horny in the basal portion arid membranous at the extremity, where 

 they cross each other. This group includes the various species 

 of Bugs. 



Hermaphrodite — Possessing the organs of both sexes. 



Homology — That relation between parts which results from their develop- 

 ment from corresponding embryonic parts, either in different animals, 

 as in the case of the arm of man, the fore-leg of a quadruped, and 

 the wing of a bird; or in the same individual, as in the case of the 

 fore and hind legs in quadrupeds, and the segments or rings and 

 their appendages of which the body of a worm, a centipede, &c., is 

 composed. The latter is called serial homology. The parts which 

 stand in such a relation to each other are said to be homologous, 

 and one such part or organ is called the homologue of the other. In 

 different plants the parts of the flower are homologous, and in general 

 these parts are regarded as homologous with leaves. 



Homoptera- — An order or sub-order of Insects having (like the Hemiptera) 

 a jointed beak, but in which the fore-wings are either wholly mem- 

 branous or wholly leathery. The Cicadas, Frog-hoppers, and Aphides, 

 are well-known examples. 



Hybrid — The offspring of the union of two distinct species. 



Hymenoptera — An order of Insects possessing biting jaws and usually four 

 membranous wings in which there are a few veins. Bees and Wasps 

 are familiar examples of this group. 



Hypertrophied — Excessively developed. 



Ichneumonidca — A family of Hymenopterous insects, the members of which 



lay their eggs in the bodies or eggs of other insects. 

 Imago — The perfect (generally winged) reproductive state of an insect. 

 Indigens — The aboriginal animal or vegetable inhabitants of a country or 



region. 



