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mass. They hatch in a fortnight, and the larva produced is, as in the case 
of the other genera, a “Triungulinus,” a little, active, three-clawed creature, 
originally detected upon "bees, and described as a special parasite, before its 
connection with these beetles was known. The Triungulinus of the blister- 
beetle is dark brown, with a white band across the middle of its body ; its 
eyes are black and prominent, and its jaws very sharp, and it has two long 
caudal bristles. M. Lichtenstein had some difficulty in getting the young 
animals to feed, but at last he tempted them with the stomachs of honey- 
bees, and then gave them the eggs and young larvae of various species of 
bees. But he found that it was necessary to associate honey with their 
animal food, otherwise they would not touch the latter, almost as if they 
were instinctively aware that honey would be absolutely requisite for their 
sustenance as soon as they had undergone their first change of skin. When 
this condition is fulfilled, however, he found that they at once inserted their 
jaws into the egg or larva before them, and increased rapidly in size. In five 
or six days they changed their skin, and gave origin to small, white, six- 
footed larvae, without caudal bristles, and with blunt jaws ; these quitted 
the animal food and devoted themselves to the honey. In five days more 
there was another change of skin ; after which the jaws were still broader and 
the eyes less marked ; and after the next change, which took place five days 
later, the eyes had disappeared, the legs and jaws had become brown and 
horny at the end, and the larva had the appearance of a small grub of a 
Lamellicorn beetle. This form is called by Mr. Riley the “ Scarabaeoid 
larva,” and it was apparently fitted for burrowing. Accordingly the insects 
in this stage were transferred to a new form of prison, in which they had a 
sufficient quantity of damp earth in which to bury themselves, which they 
proceeded to do at once, making their way nearly to the bottom of the earth 
in their tubes, and resting in a small cavity close to the wall of the tube, 
thus enabling the author to observe their subsequent proceedings. After 
remaining here for another five days they underwent a fresh change, and 
gave origin to a pupa-like creature, having four little tubercles at the anterior 
end, and three pairs of tubercles at the points where the legs had been 
situated. In this state they remained motionless through the winter, but on 
April 15 they burst their envelope, and produced, not a perfect beetle, but a 
white, grub-like creature, with rudimentary feet, and in other respects some- 
what resembling the larva which had burrowed down into the ground. In 
this condition the insect moved slowly in its cell, but ate nothing, until in 
about a fortnight, it again cast its skin and gave birth to a pupa, presenting 
all the characters of those of beetles. At first white, the pupa speedily 
became coloured ; on May 17 it was quite of a dark tint, and on the 19th 
the perfect beetle was seen in its retreat ready to emerge. The development 
had thus occupied just a year. M. Lichtenstein believes that the burrowing 
bees, such as the Halicti and Andrena ?, are those at whose expense the 
blister-beetle is nourished. — ( Comptes rendus, May 26, 1879.) 
The Gall- Aphides of the Elm. — Dr. Riley has ascertained that the natural 
history of the aphides which produce galls deforming the leaves of the 
common American Elm is exceedingly complicated. The species described 
by him is Schizoneura americana. During the winter, in the cracks in the 
bark of an elm, the leaves of which suffered much from the attacks of the 
