106 
Psyche 
[June 
with almost no labor. Is it possible that it is not dependent 
upon instinct, but in the emergency each brings to the fore all 
its intelligence and resources to cope with the situation, and 
that those which do not, die? 
At the last observation at 7 p. m., I found no. 3 ’way up in 
the top of the channel, having in my absence successfully passed 
the hard plug by biting her way around it through the soft pith. 
This compartment was an empty gallery of 3 3/4 inches, and 
she had evidently lost no time in traversing the long open stretch. 
She was already at the very top, attacking the final plug at the 
orifice. This was the “outer defence,” l/ 4 inch thick and tightly 
packed, and I was sorry, for I knew she would have a distressing 
time with it. 
At this time, 7 p. m., no. 4 was barely out of its cocoon, at 
noon it had been just half-way out; this shows that its progress 
was slow. Its movements showed, however, that it was struggling 
hard to make headway through the 3/4 inch of debris that its 
predecessor had caused to fall down upon it. It reminded me 
of a cyclone victim trying to free himself from below a pile of 
broken rubbish. By 8 o’clock the next morning, this one had 
succeeded in escaping from the debris and was up at the top, 
complacently waiting beside no. 3, while the latter was at work 
cutting her way through the last obstruction. Doubtless no. 4 
worked during the night, yet I could not quite overlook the way 
in which she sat by without disturbing herself in the least, wait- 
ing as a matter of course for the older sister to break the way for 
her. Whenever I noticed them during the forenoon the division 
of labor continued the same; no. 3 bravely struggled with the 
plug, often dropping tiny bits of it below, and digging out the 
pith bit by bit at the left side, while no. 4 quietly waited for her 
to finish her job. 
When I returned at 11 p. m. and examined the nest, I found 
that no. 3 was out of the nest, and on the floor of the jar — dead. 
With her jaws she had torn to bits the formidable final plug and 
thereby acquired her liberty, but with it had come exhaustion 
and death. In this case futile attempts had been made to 
bite away the pith beside the plug, although at the point where 
