SCIENTIFIC SURVEY. 35 



a continuous armor of angular scales, or bony plates fitting into each 

 as in the sturgeons. 



3. Ctenoids. — Those having scales with their posterior edges 

 comb-like (pectinated,) as in the perches. 



4. Cycloids. — Those with scales entire and of a circular form, as 

 in the Salmons. It seems, from this, that the first fishes formed, 

 judging from the oldest fossil remains were Placoids, and the last 

 Cycloids. 



GLOSSARY: 

 OR EXPLANATION OF SOME OF THE TERMS USED IN ICHTHYOLOGY. 



A. 



Abdominal — Belonging to the abdomen, or belly. Abdominal fins 

 are those attached to the belly part of the fish, (see fins.) An 

 order established by Linneus, having the abdominal fins placed 

 behind the pectorals. 



AcANTHOPTERYGii — Thomy or spiny fins ; from akanthos, a thorn, and 

 pferiigion, fin or little feather. Fishes having such fins on their 

 backs form one of the natural orders of fishes. 



AcANTHOPTERi — Same as the above. 



AcERATED — Pointed ; sharpened to a fine point ; needle-shaped. 



Adipose — Fatty ; fleshy. An adipose fin is one without any rays, 

 but made up of a fleshy or fatty. substance, and is generally 

 placed on the back near the tail, as in the salmon and trout. 



Anal — Relating to the vent, placed near the vent, {see fins.) 



ANACANTmNi — Literally, this means no thorns, or thornless, (from 

 the Greek ana none, and acanthus, thorn.) It is the name of the 

 second order of fishes in some systems. 



Anterior — Going before ; fore-part ; forward of something else ; 

 the opposite to posterior. 



Apodal — Without ventral fins; from a (privative) no, and pous, feet ; 

 no feet, the ventral fins being considered, in comparative anat- 

 omy, as in the place of feet, (see fins.) 



Arcade — An arch or series of arches. 



B. 



Barbel — A beard ; a slender soft filament attached to the lips, chin 



or snout of some fishes. 

 Bifurcate — Divided into four points or two forks ; twice forked. 



