142 EXPLANATION OF TERMS 



Translucid: clear: transparent enough to be seen through. 



Transparent: so clear as not to obstruct vision. 



Transverse: when the longest diameter is across the body. 



Transverse incision: = transverse sulci. 



Transverse sulci: the transverse grooves of pronotum in many Orthoptera. 



Transverse suture: in Diptera, a transverse groove extending inward from 

 the root of wing and obsolete in the middle of dorsum. 



Trapeziform: in the form or shape of a trapezium. 



Trapezium: a four-sided figure in which no two sides are parallel. 



Trapezoid -al: a four-sided plane of which two sides are parallel and two 

 are not. 



Tri-: three; a combining form. 



Triangle: in Odonata, a small, triangular cell at the junction of cubitus 

 with cubitus 1: a similar cell adjoining it basally is the internal triangle: 

 = discoidal triangle; cardinal cell; q. v. 



Tri-articulate: composed of three joints or articles. 



Tribe: a term of classification less than a sub-family: opinionative and end- 

 ing in ini; but this is not universally adhered to. 



Tri-carinate: with three keels or carinse. 



Trichogen: a hair-forming hypodermal cell in caterpillars, etc. 



Trichoptera: hairy-winged: insects with hairy primaries with many longi- 

 tudinal veins and cells, covering the broader secondaries which are usually 

 folded lengthwise ; mouth mandibulate but rudimentary ; head free ; thorax 

 agglutinate ; metamorphosis complete. 



Trichostical bristles: in Diptera, a fan-like row, situated on the meta- 

 pleura : conspicuous in some families. 



Trichotomous: divided by threes. 



Trichroism: the condition when any given part exhibits three different colors 

 in different individuals of the same species ; e. g., in Lep-idoptera, the hind 

 wings of certain Heliconids. 



Tricuspidate: ending in three points: with three cusps or teeth. 



Tridactyle -ous: having three toes or claws. 



Trifid: cleft into three parts or ends. 



Trigonal: triangular: an area bounded by a triangle. 



Trigonate: three-cornered; approximately triangular. 



Trigoneutism: where three broods occur in one season. 



Trigonulum: in Odonata, = triangle. 



Trimera: that series of Cohoptera in which there are only three tarsal 

 joints present. 



Trimerous: species which have the tarsi three-jointed. 



Trinomial: that method of nomenclature in which a varietal or subspecific 

 name follows the specific term without an intervening mark or indication 

 of its rank. 



Tripectinate: when an antenna has three branches or processes to each joint. 



Triquetral: = triquetrous. 



Triquetrous: with three flat sides. 



Tri-region'al: divided into three distinct parts or regions. 



