I03 EXPLANATION OF TERMS 



Pinnate: feather-like; cleft, like the wings of Alucita: with markings re- 

 sembling a feather : with stiff hairs or thorny processes occupying opposite 

 sides of a thin shank. 



Pinnatifid: divided into feathers, as when wings are cleft nearly to the base. 



Pistazinus: yellowish green, with a slight brownish tinge [pale green with a 

 little burnt sienna]. 



Plaga: a spot, stripe or streak of color; a longitudinal spot of irregular form. 



Plaited: longitudinally folded or laid in pleats. 



Planate: with a flattened surface. 



Plane: level, flat; applied to a surface. 



Planipennia: applied to Neuroptera in which the wings are large and laid 

 flat on the body wlien at rest ; Sialidcc, Myrmclconidcc, etc. 



Planta-ae: the basal joint of the posterior tarsus in pollen gathering Hynien- 

 optera : the soles of the posterior tarsal joints: the anal clasping legs of 

 caterpillars. 



Plantigrade: species that walk on the entire foot, not on the claws alone. 



Plantula: a lobe of the divided tarsal pulvillus ; one of the soles or climbing 

 cushions of the foot : see arolium ; pulvillus. 



Plaques: the small leathery hemelytra in some Naucorids. 



Plasma: the liquid portion of animal fluids and cells. 



Plasticity: the capacity for being formed, moulded or developed. 



Plate: any broad flattened piece or sclerite : = squame, in Coccidcc. 



Platelet: a little plate or sclerite of chitin in a membrane. 



Plates: in Coccida, the squames ; q. v.: in male Hoinoptera, a pair of pieces 

 following the last full ventral segment ; usually preceded by a short piece, — ■ 

 the valve. 



Platyptera: flat and broad-winged: an ordinal term applied to insects with 

 four net-veined wings, secondaries longitudinally folded beneath primaries ; 

 mouth mandibulate ; prothorax free ; transformations complete : Psocida, 

 Tcnnitidcc, Perlidcc and Mallophaga. 



Plecoptera or Plectoptera: plaited winged: an ordinal term applied to net- 

 veined insects in which the secondaries are longitudinally folded beneath 

 primaries; mouth mandibulate; body loosely jointed; prothorax free; meta- 

 morphosis incomplete: the term Plecoptera was used by Brauer for Perlidcs ; 

 Plectoptera by Packard for the Epiiemcrida ; there has been some confusion 

 since, and both have been used in the Brauer sense. 



Pleon: ^abdomen; q. v. 



Pleopoda: abdominal legs of larv;e : posterior legs of an adult. 



Plesiobiosis: see symbiosis. 



Plesiotype: any specimen identified with a described or named species by a 

 person other than the describer. 



Pleura: jjlural of pleuron or pleurum : the lateral sclerites between the dorsal 

 and sternal portion of the thorax : in general, the sides of the body between 

 the dorsum and sttrnum. 



Pleural areas: on the melanotum of some Hyincnoptcra. the three spaces 

 between the lateral and pleural carinne ; the ist or anterior ^ spiracular 

 area ; the 2d or central = middle pleural ; the 3d or posterior = angular area. 



