USED IN ENTOMOLOGY. 41 



rum from the humeri through the base of the wing ; separates the meso- 

 notum from the pleura. 



Dorso-ventral: in a line from the upper to the lower surface. 



Dorsulum: the mesonotum before the scutellum, with the wing sockets; also, 

 specifically, the meso-scutellum. 



Dorsum: the upper surface: in Coleoptera; often confined to meso- and 

 meta-thorax : Odonata; includes mesepisterna and meso- and meta-thoracic 

 terga : Diptcra; upper surface of thorax, limited by the dorsopleural 

 sutures laterally, the scutellum posteriorly and the neck anteriorly : Lepi- 

 doptera; the lower or inner margin of the wing. 



Draw-thread: the silk-producing gland. 



Drone: in Hymenoptera; the male bee. 



Duct: a channel, tube or canal for carrying a secretion from a gland to the 

 point of discharge. 



Ductus ejaculatorius: the single duct or tube formed by the union of the 

 vasa deferentia from each side, through which the seminal fluid is ejected 

 into the vagina. 



Dufour's gland: that gland, in Hymenoptera, that secretes the alkaline por- 

 tion of the poison carried by the sting. 



Duodenum: the chylific ventricle; also applied to the first section of the 

 digestive tract just behind entrance of malpighian tubules. 



Dupion: a cocoon spun by two silk- worms together; also the coarse silk 

 from such a cocoon. 



Duplicate -us: double. 



Duplicate-pectinate: having the branches of a bipectinated antenna alter- 

 nately long and short. 



Duplo: double, or twice. 



Durus: hard. 



Dusky: somewhat darkened; pale fuscous. 



E: as prefix, is privative and means without. 



Ears: organs of hearing, as on the first tibiae or on the first abdominal seg- 

 ment of some Orthoptera. 



Ebonine: black like ebony. 



Eburneous: ivory white. 



Ecalcaratus: without a spur. 



Ecaudate: without tails or tail-like processes: usually applied to wings: 

 = excaudate. 



Ecdysis: the process of casting the skin; moulting. 



Echinate: set with prickles. 



Ecology: the science of the relation of organisms to each other and to their 

 surroundings : = ethology. 



Ectad: extending outwardly from within. 



Ectal: belonging or relating to the outer surface. 



Ectoblast: the outer wall of a cell; the ectoderm or epiblast. 



