part from recently ejected castings.
Dr. King informs me that the majority of the before described gigantic
castings, which he found on a fully exposed, bare, gravelly knoll on the
Nilgiri Mountains in India, had been more or less weathered by the
previous north-east monsoon; and most of them presented a subsided
appearance. The worms here eject their castings only during the rainy
season; and at the time of Dr. King s visit no rain had fallen for 110
days. He carefully examined the ground between the place where these
huge castings lay, and a little watercourse at the base of the knoll, and
nowhere was there any accumulation of fine earth, such as would
necessarily have been left by the disintegration of the castings if they
had not been wholly removed. He therefore has no hesitation in asserting
that the whole of these huge castings are annually washed during the two
monsoons (when about 100 inches of rain fall) into the little
water-course, and thence into the plains lying below at a depth of 3000
or 4000 feet.
Castings ejected before or during dry weather become hard, sometimes
surprisingly hard, from the particles of earth having been cemented
together by the intestinal secretions. Frost seems to be less effective
in their disintegration than might have been expected. Nevertheless they
readily disintegrate into small pellets, after being alternately
moistened with rain and again dried. Those which have flowed during rain
down a slope, disintegrate in the same manner. Such pellets often roll a
little down any sloping surface; their descent being sometimes much aided
by the wind. The whole bottom of a broad dry ditch in my grounds, where
there were very few fresh castings, was completely covered with these
pellets or disintegrated castings, which had rolled down the steep sides,
inclined at an angle of 27 .
Near Nice, in places where the great cylindrical castings, previously
described, abound, the soil consists of very fine arenaceo-calcareous
loam; and Dr. King informs me that these castings are extremely liable to
crumble during dry weather into small fragments, which are soon acted on
by rain, and then sink down so as to be no longer distinguishable from
the surrounding soil. He sent me a mass of such disintegrated castings,
collected on the top of a bank, where none could have rolled down from
above. They must have been ejected within the previous five or six
months, but they now consisted of more or less rounded fragments of all
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