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CHAPTER II. 



HISTOKY OF THE GENUS SOLE A. 



THE flat-fishes have been always placed together in one group in all attempts to classify 

 fishes from the time of the ancient Greeks and Eomans up to the present. Thus 

 Aristotle called them i/^TraJSeig. But in ancient times other fishes of a flat shape, 

 but symmetrical, like the dorey and the skate, have often been united with them. Thus 

 Eondelet includes among the " poissons plats " the dorey and two other symmetrical 

 fishes and all the skates and rays. In the ancient and pre-Linnaean times ideas 

 of classification were somewhat vague ; the idea of genus and species existed, though 

 it was not accurately defined, but degrees of classification regularly subordinated to 

 one another could not be established by men who had little real knowledge of the 

 structure and physiology of animals. Eondelet includes all marine animals among his 

 " Poissons," yet his arrangement of the true Pleuronectidse in genera and species is 

 more similar to that which is now accepted than the classification adopted by Artedi 

 and Linnaeus. Eondelet describes the genus Rhombus with two species, one with 

 spines and the other without, the turbot and the brill ; the genus Rhomboides ; 

 Citharus with two species ; Passer with four species, Passer, the plaice, Passer quad- 

 ratulus, Passer liinanda, and Passer flesus (the flounder) ; the genus Solea, with six 

 species, Solea, the common sole, Solea oculata (la Pegouse), la Pole, Arnoglossus, Solea 

 linguki, and Hippoglossus. 



Artedi arranged all the flat fishes into one genus Pleuronectes, a name which he 

 introduced into zoology for the first time, and Linnaeus followed his example. The 

 12th edition of the " Systenia Nature " was published in 1766. The successors of 

 Linnaeus for some time continued to follow him and Artedi, merely dividing the genus 

 in an arbitrary way into subgenera. Lacepede, in his " Histoire Nat. des Poissons," 

 published in 1798, defines four subgenera of Pleuronectes, but without giving them 

 distinguishing names : the first of them comprises only the halibut and the flounder, 

 united because their eyes are on the right side and they have a curve in the lateral 

 line. Similarly, Eisso, in his " Ichthyologie de Nice," 1810, arranges the species under 

 two subgenera, according to the side on which the eyes are situated. 



Quensel in 1806 divided the genus into two, with the following definitions: 

 Plearonecte-s, having complete jaws not covered with scales ; the maxillary dilated 



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