208 University of Washington Publications in Biology [Vol.2. 



Palate. The roof of the mouth. 



Palatines. Membrane bones of the roof of the mouth, one on each 

 side extending outward and backward from the vomer. 



Palustrine. Living in swamps. 



Papilla. A small fleshy projection. 



Papillose. Covered with papillae. 



Parapophyses. The lateral projections on some of the abdominal ver- 

 tebrae for the support of ribs. 



Parietal. A bone on the top and back side of the head. 



Parotic process. A posterior lateral process of the skull formed by 

 the pterotic and opisthotic bones. 



Parr marks. The vertical color bars found on Salmonoids. 



Pectinate. Having teeth-like projections as in a comb. 



Pectoral radials. See actinosts. 



Pectoral fins. The anterior or uppermost of the paired fins, in fishes, 

 corresponding to the anterior limbs of the higher vertebrates. 



Pelagic. Living on or in the high seas. 



Pelvic girdle. The bones supporting the ventral or pelvic fins. 



Pelvic fin. See ventral fin. 



Perforate. Pierced through. 



Peritoneum. The membrane lining the abdominal cavity. 



Pharyngeal bones. Bones behind the gills and at the beginning of the 

 oesophagus of fishes. They are of various forms and almost al- 

 ways provided with teeth. 



Pharyngeal teeth. In Cyprinidae the main row of teeth on each phar- 

 yngeal bone contains 4 or 5 teeth (seldom more or less) ; inside 

 of this main row is a so-called "lesser row" which may contain 

 1 or 2 teeth or none, in the latter case being designated in 

 the formula, as for example, teeth 2:4-4:0 means 4 teeth in 

 each main (outer) row, and 2 teeth in one lesser row of one 

 side and teeth in the other lesser (inner) row. 



Pharyngobranchials. Upper elements of the branchial arches with 

 teeth. 



Pharyngognathous. Having the lower pharyngeal bones united. 



Photophores. Small bead-like organs, light colored, for production 

 of light. 



Physostomous. Having the air bladder connected by a tube with the 

 oesophagus. 



Physoclistic. Having no open duct to air bladder. 

 Pituitary body. A small organ in the ventral part of the brain. 

 Plicate. Folded ; showing transverse folds or wrinkles. 

 Plumbeous. Lead colored ; dull bluish gray. 



