IT4 GLOSSARY. 



Progna'thous (Gr. pro, forward; gnathos, a jaw). A term 



applied to those skulls in which the craniofacial angle is 



large and the upper jaw protruded. 

 Proliferate (L. proles, offspring ; few, I bear). Applied to a 



part of a plant or animal produced from an unusual portion 



of the body. 



Pro'montory (L. prdmontdrium, a mountain peak). A pro- 

 jection on the sacrum ; also a rounded elevation in the 



tympanum of the ear. 

 Prona'tion (L. pronus, facing downwards). The turning of 



the hand with the palm downwards. 

 Prona'tor te'res (L. rounded pronator). A muscle which passes 



from the post-axial condyle of the humerus to the radius, 



and which is concerned in pronation. 

 Prona'tor quadra'tus (L. square or four-sided pronator). A 



muscle which passes from the ulna to the radius, and which 



is concerned in the act of pronation. 

 Prono'tum (Gr. pro, before; notos, the back). The tergal 



portion of the prothorax in the Insecta. 



Pro-os'tracum (Gr. pro, before; ostrakon, a shell). The for- 

 ward continuation of the guard in the Belemnites. 

 Pro o'tic (Gr. pro^ before, in front of; ous, otos, the ear). A 



bone developed in some Vertebrata in front of the ear. 

 Pro'podite (Gr. pro, before ; pous, podos, a foot). The sixth 



joint of the typical limb of a Crustacean. 

 Propo'dium (Gr. pro, before ; pous,podos, a foot). The anterior 



division of the foot in some Gasteropoda and Pteropoda. 

 Proptery'gial (Gr. pro, before ; pterux, a wing). The name 



given to the anterior basal cartilage of the fins in the 



Elasmobranchii. 

 Prosence'phalon (Gr. pros, before ; enkephalon, the brain). 



The fore-brain, comprising the cerebral hemispheres and 



olfactory processes. 

 Prosobranchia'ta (Gr.pro, forward ; branchia, a gill). A group 



of the Branchiogasteropoda in which the gills occupy a 



forward position. 

 Prosopulmona'ta (Gr.flro, forward ; \^.pulmo,pulmonis, a lung). 



A group of the Pulmonata in which the pulmonary sac 



occupies a forward position. 

 Pro'state (L. pro, before ; status, set). The name of a gland 



set in front of the orifice of the male urinary bladder. 

 Pro'tagon (Gr. protos, first ; ago, I lead). A nitrogenous sub- 

 stance obtained from the brain and other tissues. 



