370 GLOSSARY OF TECHNICAL TERMS. 
lobe, which in certain lizards (and in extinct forms) is connected 
with a third or median eye. 
Pituitary body. A small ganglion in the brain. 
Planta. Sole of foot. 
Plantigrade. Walking on the sole of the foot, as do men and bears. 
Plastron. Lower shell of a turtle. 
Plicate. Folded; showing transverse folds or wrinkles. 
Plumage. The feathers of a bird, taken collectively. 
Plumbeous. Lead-colored, — dull bluish gray. 
Pollex, Thumb; in birds, the digit which bears the alula, — corre- 
sponding to the index finger. 
Polygamous. Mating with more than one female. 
Post-frontal (plates). The ones before the vertical plate. 
Post-orbital. Behind the eye. 
Post-temporal. The bone, in fishes, by which the shoulder girdle is 
suspended to the cranium. 
Precoces. Birds able to run about and feed themselves at once when 
hatched. 
Precocial. Having the nature of Precoces. 
Precoracoid. <A portion of coracoid more or less separated from the 
rest. 
Precoracoid arch. An arch in front of the coracoid in most soft-rayed 
fishes. 
Prefrontal (plates). Those in front of post-frontal. 
Premazillaries. The bones, one on either side, forming the front of the 
upper jaw in fishes. They are usually larger than the maxillaries 
and commonly bear most of the upper teeth. ~ 
Premolars. The small grinders; the teeth between the canines and 
the true molars. 
Preocular. Before the eye. 
Preopercle. The membrane bone lying in front of the opercle and 
more or less nearly parallel with it. : 
Preorbital. The large membrane bone before the eye in fishes. 
Primary. Any one of the ten (or nine) of the large, stiff quills grow- 
ing upon the pinion or hand-bones of a bird; as distinguished 
from the secondaries, which grow upon the fore-arm. 
Primary wing coverts. The coverts overlying the bases of the pri- 
maries. 
Procelian. Concave in front only. 
Procurrent (fin). With the lower rays inserted progressively farther 
forward. 
Projectile. Capable of being thrust forward. 
Protractile. Capable of being drawn forward. 
Proximal. Nearest. 
Pseudobranchie. Small gills developed on the inner side of the opercle, 
near its junction with the preopercle. 
Pterygoids. Bones of roof of mouth in fishes, behind the paiatines. 
Pubis. Anterior lower part of pelvis. 
Pulmonary. Pertaining to the lungs. 
