54 EXPLANATION OF TERMS 



occur on the outer margins of all wings and consist of scales or hair 



projecting beyond the wing membrane. 

 Frog: the articular pan; q. v. 

 Frons: = front; q. v. 

 Front: the anterior portion of head between base of antennae and below 



ocelli : in Homoptera, the vertical median area of face. 

 Frontal: referring to the front of head or anterior aspect of any part. 

 Frontal costa: Orthop'tera; a prominent vertical ridge of head which may be 



median or lateral : see median carina and lateral carina. 

 Frontal fastigium: in Orthoptera, that process of the face extending dorsad 



between the antenna? and meeting or nearly meeting the fastigium of the 



vertex in Tettigidce. 

 Frontal fissure: Diptera; the impressed line extending from the frontal 



lunule to the border of the mouth. 

 Frontal lobes: in Psyllida, two lobes or swellings more or less completely 



divided by a suture in which an ocellus is situated. 



Frontal lunule: Diptera; an oval or crescentic space above the base of an- 

 tennae in Cydorrhapha, bounded by the frontal suture. 

 Frontal processes: Diptera; = antennal process, q. v. 

 Frontal ridge: in Coleoptera; a sharp ridge on the dorsal margin of the eye, 



extending forward. 



Frontal stripe: Diptera; the middle of the front when membranous or dis- 

 . colored: = vitta frontalis. 

 Frontal suture: Diptera; separates the frontal lunule from that part of the 



head above it: in Coleoptera; = clypeal suture. 

 Frontal tubercles: in certain Aphids, are raised structures upon which the 



antennae are placed. 

 Frontal triangle: Diptera; the triangular space in males, between the eyes 



below, limited by a line drawn through base of antennae. 

 Frontal vesicle: in Odonata; that elevated area on the vertex upon which 



the ocelli are situated. 

 Fronto-orbital bristles: in Diptera; are placed on each side of the front, 



just below the vertical bristles. 

 Fugitive: soon disappearing; not permanent. 



Fulcrant: the trochanter when continued along the femur, as in Carabids. 

 Fulcrum: the chitinous envelope at the base of mouth in Diptera and 



Hymenoptera, covering the beginning of the oesophagus : any structure 



that serves as a support to another. 

 Fulgidus: shining. 



Fuliginous -osus: sooty or smoky brown [Van Dyke brown + a little black]. 

 Fulvo-eeneous: brazen, with a touch of brownish yellow [brown pink]. 

 Fulvous -us: tawny; light brown with much yellow; nearly orange [pale 



cadmium yellow + Indian red]. 

 Fumate-us: smoky gray [gray]. 

 Fumose: smoky. 



Function: the work or duty which a given part or organ normally per- 

 forms. 



