MODE OF OBSERVATION. 3 
observation. I found it convenient to have one side 
of the nest formed by a loose slip of wood, and at one 
corner I left a small door. These glass nests I either 
kept in shallow boxes with loose glass covers resting 
on baize, which admitted enough air, and yet was im- 
pervious to the ants; or on stands surrounded either 
by water, or by fur, with the hairs pointing downwards. 
Some of the nests I arranged on stands, as shown in 
Fia. 1. 
na a | 
Cw 
B 4B 
{ ] 
fig. 1. A A is an upright post fixed on a base BB. 
CC is a square platform of wood round which runs a 
ditch of water. Above are six nests, D, each lying 
on a platform E, which could be turned for facility of 
observation, as shown in the dotted lines D’ and E’. 
Thus the ants had a considerable range, as they could 
wander as far as the water ditch. The object of having 
the platform C C larger than the supports of the nests 
