GLOSSARY. 405 



Pectoral. Relating to the breast. 



Pectoral fins. The uppermost of the paired fins on fishes, usually attached to the side of the 



breast; corresponding to the anterior limbs or arms of higher animals. 

 Peduncle. See caudal peduncle. 

 Pelagic. Relating to the sea; said of fishes that inhabit the high seas, such as the mackerels 



and dolphins. 

 Peritoneum. The delicate membrane lining the ai)dominal cavity and co*^ering the intestines 



and other viscera. 

 Pharyngeal bones. Bones at the entrance to the esophagus, usually having 1 or 2 rows of 



teeth. 

 Pharynx. The throat. 

 Plicate. Folded. 



Premaxillaries. Two bones, one on each side, forming the anterior part of the upper jaw in 

 fishes; some of the teeth are usually inserted on them. 



Preopercle. A flat bone anterior to the opercle. 



Preorbital. A flat bone anterior to the eye. 



Procumbent. Lying or directed forward. 



Procurrent. Extending forward; said of a fin whose lower or anterior rays are inserted beyond 

 tlie regular base of the fin. 



Protractile. Capable of being extended or drawn forward . 



Proximal. Nearest to the base. 



Pbeudobranchiae. Small gills, usually mere rudiments, on the under side of the opercle. 



Punctate. Finely spotted. 



Pyloric coeca. Blind sacs connected with the pylorus or lower end of the stomach. 



Ray. One of the cartilaginous supports of a fin. Rays are either spiny or soft, and the latter 

 are simple or branched. 



Recurved. Turned or curved backward. 



Reticular or reticulate. Formed like a net-work. 



Retrorse. Turned or bent backward. 



Rudimentary. Undeveloped. 



Rugose. Wrinkled; rough. 



Scute. A bony or horny plate, such as exists on the sides of the crevalles. 



Septum. A thin partition. 



Serrate. Like the edge of a saw. 



Setaceous. Provided with bristles. 



Setiform. Having the form of a bristle. 



Shoulder girdle. The bony girdle, posterior to the head, to which the anterior limbs are 

 attached. 



Snout. The region between the anterior end of the head and the eyes. 



Spiracles. Respiratory opening in the sharks and rays, corresponding to the nostrils in ordi- 

 nary fishes. 



Subopercle. The bone below the opercle. 



Suborbital. Beneath the eye. 



Supplementary maxillary. A small bone placed superficially on the upper part of the maxil- 

 lary in many fishes. 



Supraorbital. Over or above the eye. 



Symphysis. Line of union of two bones, as the tip of the lower jaw (chin). 



Synonym. One of the technical names applied to a given species or genus of fish. 



Synonymy. The series of technical names applied to a given genus or species. 



Tail. In popular language, usually the caudal fin; in ichthyology either the part of the body 

 posterior to th'e vent or the part posterior to the anal fin. 



Terete. Cylindrical with tapering ends. 



Thoracic. Pertaining to the thorax or chest; said of ventral fins attached beneatli the pec- 

 torals. 



Truncate. With a square or straight margin or profile; said of the caudal fin, snout, etc. 



Tubercle. A small projection. 



Type. The specimen on which the original description of a species is based. 



Vent. The posterior opening of the alimentary canal. 



Ventral. Relating to the abdomen; said of the paired fins below or behind the pectoral fins, 

 and corresponding to the posterior limbs in higher animals. 



Vertebra. One of the bones composing the spinal column. 



Vertical. Said of the fins attached on the median line of the body; these are the dorsal, caudal, 

 and anal. 



Villiform. Slender, minute teeth arranged in compact bands or patches. 



Viviparous. Bringing forth the young alive, as for example some sharks and cyprinodonts. 



Vomer. A bone in the center of the roof of the mouth, just behind the premaxillaries; it is 

 often beset with teeth. 



