4IO 



ECONOMIC ENTOMOLOGY 



Caudal Setae. Thread-like processes at the end of the abdomen. 



Chaetotaxy. The science dealing with the arrangement and nomenclature 



of the bristles on the body of insects. 



Chitin. The material of which the hard parts of the insect body are 



formed. 



Chrysalis — id. The intermediate stage between larvae and adult in the 



butterflies (Fig. 39). 



Cilia. Fringes. 



Clavate. Club-shaped; thickening gradually toward end (Fig. 87). 



Clavus. The club of an antenna; clava and clavola; in Heteroptera 



the oblong sclerite at the base of the inferior margin of the 

 hemelytra; the knob at the end of the stigmal or radial 

 veins in certain Hymenoptera. 



Cljrpeus. The anterior median portion of the head to which the labrum 



is usually attached (Fig. 4). 



Coarctate. Contracted; compact. Applied to a pupa in which all the 



appendages are concealed in a hardened covering which is 

 usually the last larval skin (Fig. 39). 



Corium. The elongate middle section of the hemelytra which extends 



from base to membrane below the embolium (Fig. loi). 



Cornicles. Glandular tubes on the abdomen of plant-lice which secrete 



a yellowish waxy liquid (Fig. 88). 



Costa. An elevated ridge that is rounded at its crest; the thickened 



anterior margin of a wing. 



Coxa. The basal segment of the leg (Fig. 19). 



Coxal Cavity. The opening or space in which the coxa articulates. In the 



Coleoplera the coxal cavity is said to be closed when the 

 epimeron extends behind the coxa to the sternum. It is 

 described as open when the epimeron does not reach the 

 sternum (Fig. 185). 



Crenate. Scalloped. 



Cuneus. Heteroptera; the small triangular area at the end of the 



embolium of hemelytra; Odonala, the small triangle of the 

 vertex between the compound eyes (Fig. loi). 



Dorsum. The upper surface. 



Ecdysis. Moulting or casting of the skin. 



Ecology. The science of the relation of organisms to each other and 



to their surroundings. 



Elytra. The anterior leathery or chitinous wings of beetles (Fig. i8i). 



Embolitun. The narrow sclerite extending along the anterior margin of 



the hemelytra, from base to cuneus or membrane, in Heter- 

 optera (Fig. loi). 



Empodium. The small process between the pulvilli in Diptera. The bi- 



fid pseudotarsi between the claws in Coleoptera (p. 14). 



Entomophagous. Insect-feeding. 



