210 CLASSIFICATION OF FISHES. 



among all the genera of this order we yet know. The 

 plates of the body, again, although of such excessive 

 hardness, appear, from the figure, to assume the form 

 and imbricate disposition of true scales ; and this struc- 

 ture is again at. variance with all the other Plectognathes. 

 Nevertheless, these deviations in an extreme aberrant 

 type are not altogether insurmountable, under the cir- 

 cumstances of its possessing the pedunculated pectoral 

 and ventral tins of the Chironectidcs and the Lophidte, 

 joined with their small and almost vertical eyes — a 

 single ray (if we understand the description) to the 

 branchia — and the uncommon hardness of its covering:. 

 It has an obvious relationship to the genera Lepisosteus 

 and Sudis among the Salmonida >-; but whether tins is of 

 analogy or affinity we know not. The preponderance 

 of its characters, looking especially at the imperfect de- 

 velopment of the branchia, appear to us to be towards 

 those of the Plectognathes; but this must be consi- 

 dered and determined by others who have better op- 

 portunities of investigating the question. Presuming, 

 however, that Polypterus is actually related by affinity 

 to the Syngnathidce and the Lophidce, it will be seen that 

 certain analogical characters would come out, rather 

 tending to strengthen this supposition. As we have not, 

 therefore, tested the order by itself, or by that of the 

 others in the class, we shall do so in the following table: — 



Analogies of the Plectognathes and the Orders of 

 Fishes. 



Families of . , . . Orders of 



Plectogxathes. Analogies. FlSHE; ._ 



The most perfectly organised : the} 

 types with spinal rays, and with > . 

 thin membranes to the fins. J 



("The 



I S 



BaiistidcE. < types with spinal rays, and with > Acanthopteryges. 



m.' .,•_, ("Fins thick, fleshy; the ravs soft and? tt. t .„„„^.,„„„„, 



Chironectidce. \ articulated. ' j Malacopteryges. 



Lophidce. Bodv mailed : mouth with cirri Cartilagixes. 



SyngnathuUe. Tail very long, attenuated. Apodes. 



It is needless to enter further into the first two of 

 these analogies, because they must be quite apparent to 



