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maturity, owing to parental neglect. Among ants, under favorable 
conditions, the infant mortality is practically nil, so that if every 
female produced eggs the population would very soon outrun the 
means of subsistence. It has been very plausibly suggested that the 
ants regulate the supply of ‘‘queens’’ by rearing a selected number 
of female larvae on a full diet, while the great majority of them are 
so insufficiently nourished that their reproductive organs never de- 
velop. The feminine trait of taking delight in nursing the larvae 
survives, however, in its full strength in these stunted females, and 
they devote themselves passionately to the care of the little, white, 
semi-translucent grubs, which resemble a crook-necked squash in gen- 
eral form. I think I have never looked into my artificial nest at any 
time during the day or night without seeing the nursing ants employed 
in caring for the larvae. 
On October 28th, 1910, I caught a worker near my wild nest 
who was carrying about a cocoon in her mandibles. I placed her 
upon the island nest, where a quantity of other workers were wan- 
dering about, not yet having begun to excavate tunnels. There arose 
immediately a tremendous competition to nurse the cocoon. The 
lucky possessor was constantly surrounded by eager applicants for 
the privilege. Sometimes they showed their impatience by stamping 
violently on the ground or jerking their bodies forward in their un- 
controllable desire to caress the helpless pupa. A few days after- 
wards the covering was stripped off, and the pale, unfinished infant 
was carried to and fro without a moment’s peace, as one ant after 
another acquired possession of it. Every worker wanted to be good 
to it and in the end it died, killed by kindness. If the care of the 
luckless pupa had been entrusted to one nurse all would have gone 
well, but by a perversion of the nursing instinct a tragedy resulted. 
On October 16th, 1910, after the first real rain of the winter 
season, I noticed a number of ants peeping out of their hole in great 
excitement. To produce the effect of nightfall I inverted a box over 
the entrance. On raising the box after a few minutes I saw the ground 
alive with ants and among them a virgin queen, which I secured. 
This is the first capture of this phase of M. M. Mojave. The general 
coloring and markings remind one of a wasp. (Fig 1.) Although 
many nests have been searched, only two queens of this species have 
been found. 
During the hot dry spell of weather at the end of August, 1910, 
the ants.stayed underground. The entrance was almost closed with 
little clods of earth, which seems to show that the extraordinary 
large nest opening is needed not so much for ventilation as to afford 
egress for ants removing nodules. 
