WHEAT SAWFLY Wheat sawfly. (a) A small European sawfly (Cephus pygmæus) whose larva does great injury to wheat by boring in the stalks. (b) Any of several small American sawflies of the genus Dolerus, as D. sericeus and D. arvensis, whose larvæ injure the stems or heads of wheat. (c) Pachynematus extensicornis, whose larvæ feed chiefly on the blades of wheat; — called also grass sawfly.
WHEATSEL BIRD
Wheat"sel bird`. (Zoöl.)
Defn: The male of the chaffinch. [Prov. Eng.]
WHEATSTONE'S BRIDGE
Wheat"stone's bridge`. (Elec.)
Defn: See under Bridge.
WHEATSTONE'S RODS
Wheat"stone's rods. (Acoustics)
Defn: Flexible rods the period of vibration of which in two planes at right angles are in some exact ratio to one another. When one end of such a rod is fixed, the free end describes in vibrating the corresponding Lissajous figure. So called because devised by Sir Charles Wheatstone.
WHEATWORM
Wheat"worm`, n. (Zoöl.)
Defn: A small nematode worm (Anguillula tritici) which attacks the grains of wheat in the ear. It is found in wheat affected with smut, each of the diseased grains containing a large number of the minute young of the worm.
WHEDER
Whed"er pron. & conj.