GLOSSARY OF TERMS USED IN DESCRIBING FISHES. 



Abdomen. The belly; that part of a fish between the pectoral and anal fins; the cavity con- 

 taining the digestive and reproductive organs. 



Actinosts. Small bones at base of pectoral fins, corresponding to wrist bones in man. 



Adipose. Fatty; a name applied to the small fin without rays on the back of trout, catfish, 

 and various other fishes. 



Adnate. Grown together; said of a fin which is attached to the body by one side as well as at 

 the base. 



Air-bladder. A membranous sac filled with gases (oxygen, nitrogen, carbon dioxide) lying 

 along the backbone in or posterior to the abdominal cavity, corresponding to the lungs 

 of higher animals and serving the purpose of lungs in some fishes; called also swim- 

 bladder and sound. 



Anadromous. Running up; said of salt-water fishes which run up streams to spawn, as the 

 shad, the alewives, the striped bass, etc. 



Anal. Pertaining to the anus or vent; the unpaired or vertical fin on the median line behind 

 the vent. 



Antrorse. Turned or bent forward; the opposite of retrorse. 



Anus. The posterior extremity of the intestine; the vent. 



Articulate. Jointed; said of the soft fin rays. 



Barbels. Slender fleshy projections about the mouth, as in the black drum and catfishes, 

 containing nerves for touch and taste. 



Branchiae. The gills. 



Branchial. Pertaining to the gills. 



Branchiostegals. Slender bony rays forming part of the lower posterior covering for the gills 

 and supporting the branchiostegal membrane. 



Caducous. Falling oflF early or easily; said of teeth, scales, etc. 



Canine. Long conical teeth in the jaws of fishes. 



Cardiform. Coarse, sharp teeth in jaws of fishes. 



Carpus. The bones at the base of the pectoral fin, corresponding to the wrist in man. 



Catadromous. Running down; said of fishes which descend to the sea to spawn, as the common 

 eel. 



Caudal. Pertaining to the tail; the fin at the posterior extremity of the body in fishes. 



Caudal peduncle. That part of the body of a fish between the dorsal (or anal) and caudal fins, 

 usually the slenderest part of a fish. 



Cephalic. Pertaining to the head. 



Ciliated. Provided with hairs or hair-like projections. 



Cirri. Minute projections forming a fringe. 



Claspers. Organs attached to the ventral fins of male skates and sharks. 



Ccecal. Pertaining to the ccECum. 



Ccecum. A blind tube or sac connected with the pylorus — the posterior part of the stomach. 



Compressed. Flattened from side to side. 



Ctenoid. Said of scales whose posterior edge is spinous or like the teeth of a comb. 



Cranial. Pertaining to the skull. 



Cranium. The skull. 



Cycloid. Said of scales which show concentric lines or striations. 



Deciduous. Falling off or out; said of teeth and scales that are shed or easily lost. 



Decurved. Curved downward. 



Dentate. Toothed; having tooth-like processes. 



Depressed. Flattened vertically. 



Depth. The vertical diameter. 



Distal. Farthest away from base or point of attachment. 



Dorsal. Relating to the back; the fin on the back. 



Emarginate. Slightly notched at the end, as the tail of a fish. 



Fauna. The totality of the animals of a given region. 



Filament. A thread-like projection. 



Filiform. Having a thread-like form. 



Fontanelle. An opening between the bones of the skull. 



Foramen. An opening or hole. 



Furcate. Forked. 



Fusiform. Spindle-shaped. 



