The Ganoids 9 



and ventral fins, and their well-developed cerebral hemispheres, 

 very unlike those of Ganoids and approaching the Amphibian 

 type, they form a very well-defined group and one very dis- 

 tinctly separated from the Ganoids. 



" No doubt the Chondrostean Ganoids are nearly as far re- 

 moved from the Teleostei as from the Dipnoans, but the links 

 uniting these Ganoids with the Teleostei have been so fully 

 preserved in the existing fauna of the globe that the two groups 

 almost run into each other. If, in fact, we were anxious to 

 make any radical change in the ordinary classification of fishes, 

 it would be by uniting the Teleostei and Ganoids, or rather 

 constituting the Teleostei into one of the subgroups of the 

 Ganoids, equivalent to the Chondrostei. We do not recom- 

 mend such an arrangement, which in view of the great pre- 

 ponderance of the Teleostei amongst living fishes would be 

 highly inconvenient, but the step from Amia to the Teleostei 

 is certainly not so great as that from the Chondrostei to Amia, 

 and is undoubtedly less than that from the Selachii to the Holo- 

 cephali." 



Gill on the Ganoids as a Natural Group. Dr. Gill observes 

 ("Families of Fishes," 1872): "The name Ganoides (or Ganio- 

 lepedoti) was originally framed by Prof. Agassiz as an ordinal 

 term for fishes having the scales (when present) angular and 

 covered with enamel; and in the group so characterized were 

 combined the Ganoids of subsequent authors as well as the Tele- 

 ostean orders Plectognathi, Lophobranchii, and Nematognathi, 

 and (subsequently) the genus Sudis (Arapaima), the last being 

 regarded as a Coelacanth. The group has not been accepted with 

 these limits or characters. 



" But the researches of Prof. Johannes Miiller on the anatomy 

 and classification of the fishes culminated at length in his cele- 

 brated memoirs on those fishes for which he retained the ordinal 

 name Ganoidei; those memoirs have left an impression on 

 ichthyology perhaps more decided than made by any other 

 contributions to science, and that published in extenso will 

 ever be classical ; numerous as have been the modifications since 

 introduced into the system, no forms except those recognized 

 by Miiller (unless it be Dipnoi) have been interjected since 

 among the Ganoids. 



