28 EXPLANATION OF TERMS 



Coelom: the body cavity. 



Coelomic cavity: the space between the viscera and the body wall. 



Coelom-sac: the cavity containing the viscera: in embryology one of a pair of 



closed sacs, arising in the mesoderm of each segment of the embryo and 



giving rise to more or less of the ccelom of the adult. 

 Coenogonous: oviparous at one season of the year, ovoviviparous at another, 



as in Aphididcc. 

 Cceruleus -eous: sky-blue: see caeruleus. 

 Coincident: when two wing veins run together or lie, one in continuation of 



the other so as to appear like one. 

 Coleoptera: sheath-winged: an order with the primaries coriaceous, used as 



a cover only, meeting in a straight line dorsally ; mouth mandibulate ; pro- 

 thorax free ; transformations complete : the beetles : the term has also been 



applied to the two elytra together. 

 Collar: in general any structure between the head and thorax: specifically. 



in Hymenoptera, the neck ; in Diptera, may mean the neck, the sclerites 



attached to the prothorax, the prothorax itself, orits processes (ante furca) ; 



in Coleoptera, is the narrowed prothorax ; in Lepidoptcra, applied to the 



sclerites attached to the prothorax and which shield the neck. 

 Collembola: an ordinal term applied to species which are apterous; have no 



metamorphoses ; have variably developed abdominal saltatorial appendages 



and a peculiar ventral tube at base : the spring-tails. 

 Colleterial gland: see colleterium. 

 Colleterium: a glandular structure accessory to the oviduct, secreting the 



viscid material used in cementing the eggs together. 

 Collophore: the sucker-like organ extended from the underside of the abdomen 



in Collembola. 

 Collum: the neck or collar: the slender connection between head and thorax 



in Hymenoptera and Diptera; in Coleoptera, the posterior, narrow part of 



the head or even the prothorax : loosely vised. 

 Colon: the large intestine : that usually enlarged portion of the alimentary 



canal before the rectum. 

 Columella: a little rod, pillar or central axis. 

 Columnar: cylindric, but tapering toward one end. 



Comate-us: only the upper part of head, or vertex, covered with hair. 

 Commensal: one who eats at another's table: applied to species that feed on 



the surplus supply of another, without destroying the owner of the supply. 

 Commensalism: applied to this manner of living and eating together. 

 Comminute: to grind up fine: to reduce to minute particles. 

 Commissure: the nerves connecting two ganglia : the point of meeting or union 



of two bodies: a bridge connecting two bodies or structures ; e. g., tracheal 



tubes. 

 Common: of frequent occurrence: occurring on two adjacent parts: a band or 



fascia is common when it crosses both primaries and secondaries. 

 Communal: applied to life or dwelling in colonies like ants and bees. 

 Comose: ending in a tuft or brush. 

 Complanate: compressed; flattened above and below: = deplanate. 



