140 
HALF HOURS WITH INSECTS. [Packard. 
side along the tunnel under the hairs and collects in bubbles 
above the base of the legs. Along the bottom of this 
Fig. 102. 
Hydrophilus piceus, eggs and larva. 
tunnel are six pairs of spiracles into which the air passes. 
The air in the specimens we observed did not adhere to the 
Fig 103 hairs of the hind legs as Siebold says it does, nor, 
as he states in his “Comparative Anaton^,” trans¬ 
lated by Burnett, does the air for respiration as a 
rule pass under the etytra, since the spiracles are 
not situated on the upper side of the body but on 
the under, and quite a distance from the edge of 
the body. Nor does this insect breathe at all, as 
Westwood states, like Dytiscus, in which the spir¬ 
acles are situated on the upper side of the body, so 
that the air enters readily under the elytra. When it takes 
in the air the tip of the abdomen is thrust up just above 
12 
Notonecta. 
