322 VERTEBRATES: FISHES. 



eggs, and defend them with great spirit ; but most 

 abandon them as soon as laid. With few exceptions, 

 Fishes have no care of their young, but devour them 

 as readily as they do any other food. In the Sygna- 

 thi, or Pipe-Fishes, the eggs are conveyed into a pouch 

 under the abdomen or at the base of the tail of the male, 

 where they are hatched. 



Although the lowest class of the Vertebrates, their 

 varied forms, and colors which often rival those of pre- 

 cious stones and burnished gold, the wonderful power 

 and velocity of some, the wholesome food furnished by 

 many, and the exciting sport of their capture, combine 

 to render Fishes subjects of great interest to the casual 

 observer, as well as to the amateur and the professional 

 naturalist. 



The number of known species of Fishes is about ten 

 thousand. According to the earlier writings of Agassiz, 

 they are divided into four orders, the scales being taken 

 as the basis of classification, as follows : Ctenoids, em- 

 bracing fishes which have the scales toothed on the edge, 

 as Perch, Breams, Bass, and the like ; Cycloids, comprising 

 fishes whose scales are rounded and smooth on the edge, 

 as Salmon and Cod ; Ganoids, embracing fishes with en- 

 amelled scales, as the Gar-pike ; and Placoids, fishes with 

 fine point-like or stellate scales, as Sharks and Skates. 



Cuvier divides fishes into two great groups, Bony 

 and Cartilaginous Fishes, which together include nine 

 orders ; and since so many of the books upon natural 

 history to which the student may have occasion to 

 refer follow him more or less closely, and as there is 

 no generally accepted classification of this important 

 group of animals, I have thought it best to adhere 

 mainly to his arrangement 



Bony Fishes, or Fishes proper, are those with a true 

 bony skeleton, and include six orders, as follows : 



