USED IN ENTOMOLOGY. 149 



Vertex: the top of the head between the eyes, front and occiput: in bees, 

 that part of the head adjacent to and occupied by the ocelli: in Notonectids, 

 " the imaginary anterior margin of the notocephalon." 

 Vertexal: occurring on or near the vertex, or directed toward it. 

 Vertical cephalic bristles: in Diptcra, are two pairs, inner and outer, inserted 

 more or less behind the upper and inner corner of the eye ; erect, or the 

 inner pair convergent, the outer pair divergent. 



Vertical margin: in Diptera, the limit between front and occiput. 



Vertical triangle: in (^ Diptera, the small triangle upon which the ocelli are 

 situated ; limited behind by vertex, in front by eyes. 



Verticil: one of the whorls of long fine sensitive hair arranged symmetrically 

 on the joints of the antennae in certain Diptera. 



Verticillate: placed in whorls: antennae in which the joints have a circle of 

 long, fine hair as in Cecidomyiids. 



Vesicant: blistering: able to produce a blister. 



Vesicle of penis: in Odonata, a sac with chitinous walls, attached to the 

 sternum behind the penis. 



Vesicles: little sacs, bladders or cysts: applied to extensible organs producing 

 odors or secretions, as in some beetles and caterpillars. 



Vesicular: bladder-like: beset with spherical prominences. 



Vesicula seminalis: see seminal vesicles. 



Vestibule: the space around the ovipositor formed by the projecting margins 

 of the surrounding segments : the space between the occluding structure of 

 the spiracle and the valve opening into the trachea itself. 



Vestigial: small or degenerate: only a trace or remnant of a previously func- 

 tional organ. 



Vestiture: the surface clothing, whether of a hairy or scaly character. 



Vexhillum: in Hymcnoptera, an expansion on the tip of tarsi of certain fos- 

 sorial groups. 



Vibrant: having a rapid motion to and fro. 



Vibratile: formed for vibratory motion: used to express the almost con- 

 tinual movement of the antennae of some Hynioioptcra. and the wings 

 of some Diptcra. 



Vibrissae: curved bristles or hairs in some Diptera, situated between the 

 mystax and the antennae : whiskers. 



Villi: soft hairs or papillate processes: plural of villus; q. v. 



Villose-ous: soft-haired or clothed with soft, short hair. 



Villus: a short, hair-like or papillate process on the surface of certain ab- 

 sorbent and sensory organs. 



Vinous: wine-color: a deep, transparent red-brown, like claret [purple 

 madder]. 



Violaceous: violet colored; a mixture of blue and red [violet carmine]. 



Virescent or Viridescent: greenish or becoming green. 



Viridis: green, like verdigris [French blue + chrome yellow -f white]. 



Viscera: the internal organs of the body. 



Visceral: relating or attached to the viscera. 



Viscid: sticky: covered with a shiny, resinous or greasy matter. 



