Scientific American Supplement, No. 643 | Page 8

carefully followed, I found it soon
swam, and at length got the long neck-like appendage of Amphileptus

anser!
Here then was the cup or calyx of a definite vorticellan form changing
into (?) an absolutely different infusorian, viz., Amphileptus anser!
Now I simply reported the fact to the Liverpool Microscopical Society,
with no attempt at inference; but two years after I was able to explain
the mystery, for, finding in the same pond both _V. convallaria_ and
_A. anser_, I carefully watched their movements, and saw the
Amphileptus seize and struggle with a calyx of convallaria, and
absolutely become encysted upon it, with the results that I had reported
two years before.
And there can be no doubt but this is the key to the cases that come to
us again and again of minute forms suddenly changing into forms
wholly unlike. It is happily among the virtues of the man of science to
"rejoice in the truth," even though it be found at his expense; and true
workers, earnest seekers for nature's methods, in the obscurest fields of
her action, will not murmur that this source of danger to younger
microscopists has been pointed out, or recalled to them.
And now I bid you, as your president, farewell. It has been all pleasure
to me to serve you. It has enlarged my friendships and my interests, and
although my work has linked me with the society for many years, I
have derived much profit from this more organic union with it; and it is
a source of encouragement to me, and will, I am sure, be to you, that,
after having done with simple pleasure what I could, I am to be
succeeded in this place of honor by so distinguished a student of the
phenomena of minute life as Dr. Hudson. I can but wish him as happy a
tenure of office as mine has been.
* * * * *

INQUIRIES REGARDING THE INCUBATOR.
P.H. JACOBS.

Space in the Rural is valuable, and so important a subject as artificial
incubation cannot perhaps be made entirely plain to a novice in a few
articles; but as interested parties have written for additional information,
it may interest others to answer them here. Among the questions asked
are: "Does the incubator described in the Rural dispense entirely with
the use of a lamp, using at intervals a bucket of water to maintain
proper temperature? I fear this will not be satisfactory unless the
incubator is kept in a warm room or cellar."
All incubators must be kept in a warm location, whether operated by a
lamp or otherwise. The warmer the room or cellar, the less warmth
required to be supplied. Bear in mind that the incubator recommended
has four inches of sawdust surrounding it, and more sawdust would still
be an advantage. The sawdust is not used to protect against the outside
temperature, but to absorb and hold a large amount of heat, and that is
the secret of its success. The directions given were to first fill the tank
with boiling water and allow it to remain for 24 hours. In the meantime
the sawdust absorbs the heat, and more boiling water is then added
until the egg-drawer is about 110 or 115 degrees. By this time there is a
quantity of stored heat in the sawdust. The eggs will cool the drawer to
103. The loss of heat (due to its being held by the sawdust) will be very
slow. All that is needed then is to supply that which will be lost in 12
hours, and a bucket of boiling water should keep the heat about correct,
if added twice a day, but it may require more, as some consideration
must be given to fluctuations of the temperature of the atmosphere. The
third week of incubation, owing to animal heat from the embryo chicks,
a bucket of boiling water will sometimes hold temperature for 24 hours.
No objection can be urged against attaching a lamp arrangement, but a
lamp is dangerous at night, while the flame must be regulated
according to temperature. The object of giving the hot water method
was to avoid lamps. We have a large number of them in use (no lamps)
here, and they are equal to any others in results.
With all due respect to some inquirers, the majority of them seem
afraid of the work. Now, there is some work with all incubators. What
is desired is to get rid of the anxiety. I stated that a bucket of water
twice a day would suffice. I trusted to the judgment of the reader

somewhat. Of course, if the heat in the egg drawer is 90 degrees, and
the weather cold, it may then take a wash boiler full of water to get