Series Ostariophysi 395 
long barbels about the mouth strongly suggest affinity with 
the catfishes. The scales are small, the pharyngeal teeth few, 
and the air-bladder, as in most small catfishes, enclosed in a 
capsule. The loaches are all bottom fishes of dark colors, 
tenacious of life, feeding on insects and worms. The species 
often bury themselves in mud and sand. They lie quiet on 
the bottom and move very quickly when disturbed much after 
the manner of darters and gobies. Species of Cobitis and Mis- 
gurnus are widely distributed from England to Japan. Nema- 
chilus barbatulus is the commonest European species. Cobitis 
tenia is found, almost unchanged, from England to the streams 
of Japan. 
Remains of fossil loaches, mostly indistinguishable from 
Cobitis, occur in the Miocene and more recent rocks. 
From ancestors of loaches or other degraded Cyprinide we 
may trace the descent of the catfishes. 
The Homalopteride are small loaches in the mountain streams 
of the East Indies. They have no air-bladder and the number 
of pharyngeal teeth (10 to 16) is greater than in the loaches, 
carp, or minnows. 
