The Nematognathi, or Catfishes 405 
with the mailed Loricariide they 
form a conspicuous part of the 
fish fauna. 
Fossil Catfishes—Fossil catfishes 
are very few in number. Siluride, 
allied to Chlarias, Bagarius, Hetero- 
branchus, and other fresh-water 
forms of India, are foundin the late 
Tertiary rocks of Sumatra, and 
catfish spines exist in the Tertiary 
tocks of the United States. Verte- 
bree in the Canadian Oligocene have 
been referred by Cope to species of 
Ameturus (A. cancellatus and A. 
maconnelli). Rhineastes peltatus 
and six other species, perhaps allied 
to Pzmelodus, have been described 
by Cope from Eocene of Wyoming 
and Colorado. Bucklandium diluvir 
is found in the Eocene London 
clays, and several species apparently 
marine, referred to the neighbor- 
hood of Tachysurus or Arius, 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 pre 317 —LZoricaria aurea 
Steindach- 
from the primitive Characins. ner, a mailed Catfish from Rio Meta, 
; Venezuela. Family Loricariide, 
(After Steindachner. ) 
toe 
a sa 
= ap aw i ae 
a er ae ll et a le 
Cw es a i i sil Lad ba Cal aid bat is Se aah 
DS 
Ss ee 
