Medical Officers of the Army of India.
midden and all the seeds found in the granaries are beautifully clean. I have
never found any débris of insects in the middens, nor have I ever noticed these
ants carrying insects into their nests. If an insect is placed near them they do
not, as a rule, take much notice of it. For a long time after .I first began to
observe these ants I failed entirely to find a perfect granary, although I frequently
found a few seeds in the earth turned up. The reason of my want of success
lay in my failing to understand the structure of the nest. After a time I gave
up digging down on the main entrance and took to making tentative thrusts
with the trowel in various directions at various distances from the opening
to the nest, and often with success. It was not, however, until the 27th October
1889 that I succeeded in obtaining an entire undamaged granary. This I dug
up from a nest of H. criniceps in the clayey soil in the Puri Jail garden. This
granary was at the end of an almost horizontal passage; in shape irregularly
round and somewhat larger than a hazelnut. Its walls were firm and it contained
three hundred and five seeds of Amaranthus gangeticus, grown as a vegetable
in the garden and in seed at the time, and twenty-two seeds of Scirpus barbatus,
of which only a few plants could be seen near the nest. This was, I think, a
small granary. I have seen some which must have been as large as a walnut
when entire. Moggridge speaks of granaries as large as a gentleman's gold
watch which he found in the nests of Atta barbara.
It is, of course, impossible to count all the seeds in any one nest, but—mak-
ing allowance for chaff representing grain used for daily consumption—at the
end of the cold season a large nest must, judging from the amount of chaff on
the midden, contain a fairly large store.
My observation diary shows that the ants worked regularly from the time I
first noticed them, in January, until the end of March 1889. All through the hot
months (April, May) and during the early part of the "rains" the ants remained
quiet within their nests; but about the 18th June there was a spell of fine
weather following after rain, and I find the following entry :—
"Nest of H. criniceps in Police compound. Some ants came out and collected
seeds from a small patch of Cynodon dactylon, about ten yards away from the
nest." Rain came on again, and from the 23rd June to the l0th July no ants
were to be seen.—July 10th : " Two or three days fine weather, have brought out
H. scabriceps in the Jail compound. Judging by the number of nests seen at
work during the cold weather, I think that the H. scabriceps here referred to and
the. H. criniceps, who were seen harvesting in June, must have been forced to
come out as supplies were running short."— July 28th : " About the loth rain set
in again, driving back the ants; rained steadily till the 28th. This day fine, but
though other ants that do not Store were seen, Holcomyrmex was not seen."
All through the cold season of 1889-90 the ants worked steadily. Generally
speaking, then, the period of active work is from September to April, when the
heat compels the ants to retire into the deeper parts of the nest,where they
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