GLOSSARY 279 



parts, and other portions of the head, are supposed to be modified 

 legs, and to represent the appendages of several segments, so 

 that it follows that the head is made up of several segments 

 coalesced. 



Hemiptera. An order or sub-order of insects which includes the 

 various species of Bugs. They agree with the succeeding order, or 

 sub-order, Homoptera in the peculiar structure of the mouth, but 

 differ as regards their wings. In Hemiptera the front wings are 

 horny or leathery in the basal portion and membranous at the 

 extremity, where they overlap each other when at rest ; in 

 Homoptera they are membranous throughout, and do not overlap. 

 Sometimes wings are wanting irrboth orders. 



Homoptera. The Cicadoe, Frog-hoppers, and Aphides, or Scale insects 

 are well-known examples. See Hemiptera. 



Horns. See Antennae. 



Hymenoptera. Membrane-winged an order of insects possessing 

 usually four membranous wings slightly veined. To this group 

 belong some of the most interesting insects gall-flies, saw-flies,' 

 ichneumons, and above all, ants, bees and wasps. 



Ichneumonida. A great family of Hymenopterous insects, the females 

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



Imago. The perfectly developed and reproductive state of an insect 

 (usually winged). 



Imbricate. In insects, applied to scales or plates which overlap each 

 other like the tiles of a house. 



Insecta. In its restricted sense this term is applied to those animals 

 characterised by the possession of only six legs the Hexapoda or 

 six-footed. They form the largest class of that great division of 

 the animal kingdom formerly called Articulata, but for which 

 the term Arthropoda (joint-footed) is now generally adopted. 

 Insect comes from two Latin words, ?'//, into, and sccc, to cut, and 

 refers to the fact that the body of the animals thus indicated 

 appears cut or divided transversely into a series of rings or 

 segments. 



Insectivorous. Feeding upon insects. 



[ungermanniece. A family of the Hepaticce or Liverworts in which 

 usually a slender stem bears two-rowed minute leaves. Nearly 

 related to the Musci or Mosses. 



Labiutn The under lip, the second transverse plate, which bounds 

 the posterior part of the mouth. Its appendages are called labial 

 palpi. 



Labrum. The upper lip, constituting the anterior boundary of the 

 mouth. 



Lamina. A thin plate or sheet-like piece ; the flatly expanded blade 

 of a leaf the most essential part is so called. 



Larva. The second of the four principal stages of insect-life ; the first 

 condition of an insect at its emergence from the egg. During this 

 state the growth of the insect is undergone. 



Lateral. Appertaining to the side of the axis. 



Legs. Insects are hexapodous, or provided with three pairs of legs. 



