i86 



The Nematognathi, or Catfishes 



1 



with the mailed Loricariidcs they 

 form a conspicuous part of the 

 fish fauna. 



Fossil Catfishes. Fossil catfishes 

 are very few in number. Silurida, 

 allied to Chlarias, Bagarius, Hetero- 

 branchus, and other fresh-water 

 forms of India, are found in the late 

 Tertiary rocks of Sumatra, and 

 catfish spines exist in the Tertiary 

 rocks of the United States. Verte- 

 bras in the Canadian Oligocene have 

 been referred by Cope to species of 

 Ameiurus (A. cancellatus and A. 

 maconnelli}. Rhineastes peltatus 

 and six other species, perhaps allied 

 to Pimelodus, have been described 

 by Cope from Eocene of Wyoming 

 and Colorado. Bucklandium diluvii 

 is found in the Eocene London 

 clays, and several species apparently 

 marine, referred to the neighbor- 

 hood of T achy sums or Arms, are 

 found in Eocene rocks of England. 



There is no evidence that the 

 group of catfishes has any great 

 antiquity, or that its members were 

 ever so numerous and varied as at 

 the present time. The group is 

 evidently derived from scaly ances- 

 tors, and its peculiarities are due 

 to specialization of certain parts 

 and degeneration of others. 



There is not the slightest reason 

 for regarding the catfishes as direct 

 descendants of the sturgeon or 

 other Ganoid type. They should 

 rather be looked upon as a degener- 

 ate and highly modified offshoot p IO 



from the primitive Characins. 



ner, a mailed Catfish from Rio Meta, 

 Venezuela. Family Loricariidce. 

 (After Steindachner.) 



