Glossary 



Largely because of uncertainty and confusion con- 

 cerning anatomical homologies within the Insecta, 

 many of the terms used in entomology cannot be 

 defined so as to have universal application throughout 

 the Class. For this reason such terms used herein 

 have been defined for the purposes of this work only. 

 Many of the terms used in the keys are adequately 

 defined in the introductory parts of the various chap- 

 ters and others are explained by illustrations. The 

 following list is an attempt to define all other terms 

 with which some readers might not be familiar. For 

 definitions of terms not included here the reader is 

 referred to general works on the group to which the 

 term applies, to textbooks of general entomology, or to 

 J. R. de la Torre-Bueno, A Glossary of Entomology, 

 Brooklyn Entomological Society, 1937. Most latin 

 terms are given in the singular. Plural forms are as 

 follows: for words ending in us — i (stylus, styli); 

 a — ae (fossa, fossae); urn — a (notum, nota); on — a 

 (elytron, elytra); is — es (penis, penes). 



Acetabulum. The cavity into which an appendage is 

 articulated; specifically, a coxal cavity. 



Aciculate. Appearing as if superficially scratched with 

 a needle. 



Acuminate. Tapering to a long point. 



Aedeagus. In male insects, the intromittent organ 

 or penis. 



Aeneous. Bright brassy or golden green color. 



Alula. In certain Diptera, the basal lobe along the 

 posterior margin of the wing, also called the axil- 

 lary lobe. 



Alutaceous. Rather pale leather brown; covered with 

 minute cracks like the human skin. 



Alveolate. Furnished with cells or alveoli; deeply 

 pitted. 



Amphipneustic. In insect larvae, characterized by 

 having only the first thoracic and the last one or 

 two pairs of abdominal spiracles open and functional. 



Anal area. The posterior part of a wing supported by 

 the anal veins. 



Anal hooks. In Trichoptera larvae, the hooklike claws 

 borne on the anal prolegs. 



Anepisternal suture. In certain Diptera, a suture divid- 

 ing the episternum (=mesopleuron of fig. 14:2/;) into 

 an upper part (anepisternum) and lower part (kate- 

 pisternum). 



Ankylosed. Grown together at a joint. 



Annuliform. In the form of rings or ringlike segments. 



Arculus. In some insect wings, especially in Odonata, 

 a transverse vein between the radius and cubitus 

 formed by the oblique basal part of the media and 

 a true cross vein. 



Asperate. Roughened. 



Atrium. Any chamber at the entrance of a body open- 

 ing; a chamber just within the spiracle into which 

 the spiracular opening leads, and before the occlud- 

 ing membrane of the trachea. 



Auricles. Somewhat earlike outgrowths from the sides 

 of the second abdominal segment of some male 

 Anisoptera. 



Basal space. In Odonate wings, the clear space or 



cell bounded distally by the arculus; also called 



the basilar space and median space. 

 Basitarsus. The proximal or basal segment of the 



tarsus. 

 Bicuspidate. Having two cusps or points. 

 Bifid. Cleft or divided into two parts; forked. 

 Biforous. Of spiracles, having two openings. 

 Bilamellate. Having or divided into two lamellae or 



plates. 

 Bothriothrichia. In Collembola, very fine sensory hairs 



arising from cuplike pits in the integument. 

 Bucculae. In Ilemiptera, elevated plates or ridges on 



the under side of the head, on each side of the 



rostrum. 

 Bulla. A blister or blisterlike structure; in mayflies, 



one or more weak spots which may be present in 



some of the principal wing veins, appearing as 



weakly sclerotized dilations of the veins. 



Callosity. A thick swollen lump, harder than its sur- 

 rounding area. 



Calypteres. In certain Diptera, the two basal lobes 

 at the posterior margin of the wing, termed individ- 



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