EXTRACTS FROM FOREIGN PERIODICALS. 
45 
membrane, there was a cylindrical body, seven inches in length, and about one 
inch thick. This organ was' white, and of a mammillary structure, porous, and 
resembling a cellular sponge. With gentle pressure it emitted a milky fluid. On 
the outside of this organ, I observed heads of young Serpents about an inch in 
length. They were so small and tender, that in extracting them from their cells, 
I crushed several; but I succeeded in getting out a few, measuring from three to 
six inches in length, and of the thickness of a knitting-needle. The Serpent was 
killed with a pointed stake, which passed across the body, bruising part of the 
organ containing the young. These latter were also injured, so that I could not 
ascertain their exact number ; but there were between ten and twenty. They 
had evidently never left their mother’s body, nor were they capable of feeding on 
anything but liquids, and even that not of their own accord. I therefore con¬ 
cluded that the mammillary organ was the place in or ^ear which they com¬ 
menced their existence, and which, at a certain stage of their growth, supplied 
them with nourishment. The following fact tends to confirm this opinion: — 
Several years afterwards I examined a number of young Serpents of a different 
genus, and found them much larger, and considerably stronger and more lively 
than those taken from the body of the water serpent.— Dr. Sillimans American 
Journal.^ voL xxiv. 
5.—The Tbue Cause of the Sound produced by Insects in Flying.— 
It is generally believed, both by men of science and by the vulgar, that the buz¬ 
zing” of insects in flight is caused by the vibration of their wings. Dr. Hermann 
■Burmeister, in a paper on this subject published in the Annalen der Physik 
und Chemie.^ combats that notion, and states, that it is really produced by the 
contact of the air with certain air or respiration holes in the thorax, the sound 
being assisted and modified by the motion of the wings, and being produced much 
in the same manner as the notes of a flute. The Doctor proves that the wings 
alone cannot be looked to as the cause of the humming, by its being still heard 
when the wings are entirely removed, and the insect is held by the legs; and he 
demonstrates that the above-mentioned air-holes are the true whistles —for to such 
they may be compared—by the fact, that when those tubes are filled with gum, 
and the insect flies away, the sound is no longer heard. True, the animal can 
only survive this operation a short time, from the impossibility of breathing ; but 
Dr. Burmeister considers that the experiment satisfactorily points out the truth 
of his views. In these opinions—we might call them—Dr. B. is opposed by 
M. SiLBERMANN, and supported by MM. Dumeril, Schelver, and Chaerier.— 
Those who desire a more minute account of Dr. Burmeister’s discovery, are 
referred to the German work, Annalen der Physik und Chemiej vol. xxxviii., or 
to the translation of the Professor’s paper, in Taylor’s Scientific Memoirs.^ vol. i. 
p. 877. 
