THE CONTROL OF INJURIOUS INSECTS 



411 



Epistemum. The anterior and larger lateral thoracic sclerite between the 



sternum and notum (Fig. 18). 

 Eruciform. Caterpillar-like in appearance (Fig. 38). 



Evaginate. Extruded by eversion; turned inside out when extruded. . 



Exserted. Protruded. 



Foveola — ae. A pit-like shallow depression. 



Frenulum. The spine, simple in males, compound in females, arising 



from the base of secondaries in many Lepidoplera, whose 



function it is to unite the wings in flight (Fig. 120). 

 Front. Anterior portion of the head between the base of antennae 



and below the ocelli (Fig. 2). 

 Frontal Lunula. Diptera; an oval or crescentic space above the base of antennae 



in Cyclorrhapha, bounded by the frontal suture. 

 Gena. Cheek; that portion of the head below the eyes on each side 



extending to the gular suture (Fig. 2). 

 Genitalia. External organs of reproduction and their appendages (p. 



23)- 



Halteres. The poisers or balancers; capitate movable filaments in 



Diplera, situated one on each side of the thorax and repre- 

 senting rudimentary hind wings (p. 15). 



Hermaphrodite. A bisexual individual. 



Heterogamy. Alternation of generations, two sexual or a sexual and a 



parthenogenetic. 



Hibemaculum. A tent or sheath in which a larva hibernates. 



Histogenesis. The formation and development of tissue. 



Histolysis. The degeneration and dissolution of organic tissue. 



Hyper- The case in which an insect passes through more than the 



metamorphosis. normal stages of development (Fig. 40). 



Hjrperparasite. A parasite that is parasitic upon another parasite. 



Imago. The adult or sexually mature insect. 



Instar. The period or stage between moults in a larva (Fig. 38). 



Integument. The outer covering to the insect body. 



Labium, The lower lip (Fig. 7). 



Labrum. . The upper lip (Fig. 4). 



Lacinia. The inner lobe of the first maxilla, articulated to the stipes, 



bearing brushes of hairs or spines (Fig. 6). 



Lamellate. Divided laterally into distinct leaf-like plates (Fig. 183). 



Larva. The second stage in the development of the insect, follows 



immediately after the egg stage. 



Macrochaetae. The long bristles occurring singly on the body of Diptera. 



Maggot. The footless larva of Diptera (Fig. 38). 



Mandibulate. With jaws or mandibles. 



Maxilla — ae. Jaws; one on each side of the mouth immediately beneath 



the mandibles (Fig. 6). 



