No. 400. ] IE PSFYCHOLOUPF OF- FISHES. 277 
plain view without exciting any interest, unless it comes in 
close proximity to the head of the fish, when it is located with 
precision and secured. The action is a very strong contrast to 
that of a sunfish, which depends on its eyes to locate its prey. 
A Gammarus seen swimming rapidly through the water and 
approaching a Chologaster from behind and below was captured 
by an instantaneous movement of the Chologaster, when it 
came in contact with its head. The motion brought the head 
of the Chologaster in contact with the stem of a leaf, and 
Fic. 1.— The Snowy Grouper (Epinephelus niveatus), juv. Photographed from life 
by R ldt. 
instantly it tried to capture this also. Since the aquarium was 
well lighted, the leaf in plain sight, it must have been seen and 
avoided if the sense of sight, and not that of touch, were 
depended upon. 
“In Amblyopsis, the largest of the blindfishes of the Ameri- 
can caves, the batteries of tactile organs form ridges projecting 
beyond the general surface of the skin. Its prey, since it lives 
in the dark and its eyes are mere vestiges, is located entirely by 
its tactile organs. This is done with as great accuracy as could 
be done with the best of eyes in the light, but only when the 
prey is in close proximity to the head. Coarser vibrations in 
