SIR JOHN LUBBOCK ON ANTS, BEES, AND WASPS. 123 
&c., were able to perceive light of different wave-lengths, 
and that their eyes were sensitive to the ultra-violet rays 
much beyond our limits of vision. His observations do not in 
any way controvert these deductions : indeed the argument by 
which (p. 234) he endeavours to prove that the effect is due 
to true light and not to warmth, presupposes that sensations 
which can be felt by the general surface of the skiu are still 
more vividly perceived by the special organs of vision. 
Prof. Gfraber’s observations have been followed up by 
M. Porel *. He took fifteen specimens of Camponotus ligni- 
perdus , which is a large species and, moreover, possesses the 
advantage, for this purpose, of having no ocelli, and carefully 
covered the eyes with opaque varnish. He then placed them in 
a box with ten normal specimens of the same species (to which 
he subsequently added five more), and covered over one half of 
the box with cardboard and the other half with a layer of water. 
In this way the one half of the box was darker than the other, 
but the temperature of the two sides was approximately equal. 
In four experiments the numbers were as follows : — 
Under the cardboard. 
Under the water. 
Hoodwinked Ants. 
Normal Ants. 
Hoodwinked Ants. 
Normal Ants. 
3 
9 
12 
1 
13 
7 
3 
3 
9 
9 
5 
1 
3 
8 
12 
2 
— 
— 
— 
— 
28 
33 
32 
7 
It will be seen that a very large majority of the normal ants in 
every case -went under the cardboard ; while it was practically 
indifferent to the hoodwinked ants in which side of the box they 
rested. Moreover, every time the water and the cardboard were 
transposed, the normal ants were much excited aud began run- 
ning about to avoid the light, while the hoodwinked ants were 
quite unaffected. 
These experiences therefore proved that the varnish did, in 
fact, render the ants temporarily blind, their instincts being in 
other respects unaffected. 
He then replaced the cardboard aud water by a solution of 
* Rcc. Zool. Suisse, 1887. 
