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Psyche 7:3-4, 1894.

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BIOLOGICAL NOTES ON AMERICAN GRYLLIDAE.
BY SAMUEL H. SCUDDER, CAMBRIDGE, MA.SS.
The burrows of this mole cricket are
in the main very superficial, lying just beneath the surface of the soil and run- ning in entirely irregular directions.
The insects seem to push their way
where the soil yields most readily and
take advantage of natural furrows and
crevices. The burrows are generally
so near the surface that the earth is
pushed up above them into ridges
which can be easily traced, and when
the soil dries after a rain portions of the ridges fall in and expose the burrows.
They frequently fork and occasionally
turn abruptly downward into blind
passages, in which I have failed to find anything. Apparently one insect, or at
most a pair, $ and 9, occupy a single
burrow, and males are rarely found
nearer together than thirty feet, never
apparently nearer than ten or fifteen
feet. Rathvon, however, says (Rep.
dep. agric,, 1862, 378) that in a
meadow near Lancaster, Penn., over a
hundred specimens were once taken in
a piece of ground about six feet square. Usually the burrows are just large
enough for the crickets to move in (and
these insects move backward as readily
as forward) ; but they occasionally
enlarge into lateral chambers seldom
larger than a pigeon's egg, which
enables them to turn around; and in
such chambers the eggs are laid in
masses of a hundred or thereabouts
adhering to the rootlets of Potentilla
and other plants. The eggs are spher-
ical, white or almost colorless, and
have a diameter of 0.7 mm. The newly
hatched larva can leap like a Tridac-
tylus.
Messrs. Sanborn and Thaxter once
found mature specimens in burrows of
Gryllotal'u borealis on the shores of
Winter Pond, in Winchester, Mass. I
found on visiting the spot that their own burrows were made in gravelly, sandy
soil and were very superficial, not more than an inch below the surface. I saw
one come out of its burrow, which it
did rather slowly, but as soon as its
body was three-fourths in sight, it
leaped away. They leap in a lively
manner to the distance of one or two
yards ; and when disturbed move either
backward or forward with sudden starts
after the manner of Gryllotalpa. The




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[January 1894.
burrow from which the specimen was
seen to emerge was 1.5 mm. in diam-
eter and at first vertical. Early in
October more young than mature were
found, but the young were mostly
pupae though scarcely half the size of
the adult; the two sexes seemed to be
equally common.
The testes of the male are so situated
that the upper rounded tips lie at the
base of the fore-legs, i. e., they just
extend into the prothorax; they are
approximated, the smaller front lobe
whitish, the posterior brownish and
those of opposite sides are separated by about half their transverse diameter.
What appears to be an undescribed
species of Gryllodes, allied to G.
abortivus, was found by Mr. C. J.
Maynard in Florida in an interesting
position. As I have only a single spec-
imen, a female pupa, it is not possible
to determine the species more definitely. Mr. Maynard writes me that when at
Jacksonville in January, 1869, he
observed small heaps of freshly moved
sand about an inch and a half high,
removing which with care he came to a
small hole ; this he followed to an
oblong chamber near by, near the sur-
face of the ground, about two inches
long, one wide and three-quarters of an
inch deep, on the floor of which were
scattered bits of leaves and grass. At
each extremity of this chamber (the first discovered) was found a vertical burrow
about three inches in depth, one of them empty and at the bottom of the other
"a large blue black beetle with immense
jaws." In other similar chambers only
one vertical burrow was found, from
three to six inches in depth, and this
inhabited at the very bottom by this
cricket. The chamber was made in the
close vicinity of a plant closely resem- bling our common dandelion and the
burrows penetrated between the roots of
the same; the bits of leaf found in the
chambers were also of the same plant.
It is to be hoped that future observers
in the south will follow out this clew
and obtain the perfect insect for closer determination. At some future time
I hope to publish a sketch of the
burrow and surroundings made by Mr.
Maynard .
In preparing for oviposition, the
female, standing head upward, first
removes or scrapes the bark of a rasp-
berry or other shoot with its jaws at the point where she wishes to insert an egg. Then, bringing both hind tarsi forward
to their utmost so as to approach the
head, the body, without moving the hind
tarsi, is extended forward until hind
femora and tibiae are at right angles, tlie ovipositor is placed at the angle the eggs will subsequently have in the stem and
its point is then exactly at the centre of the bitten portion. While the legs now
clasp the stem tightly, the ovipositor is worked with a slight upward and
downward movement and the body at
the same time swayed gently from side
to side. The hole drilled, the egg is
laid without previously withdrawing the




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January 1894.1 ps TcHE. 5
ovipositor, and during this latter move- ment the anal cerci tremble slightly.
Two operations, including both drilling
and oviposition, which were timed, took
six and a half and five and a half
minutes respectively. As soon as one
egg is laid, the female proceeds to attack the bark again in a new place at a very
short remove from and above the other,
and uses the bits of bark torn off to
conceal the opening of the hole below,
fastening them in place by the aid of its ' Lmolasses," so that when it hardens it presents the rough appearance one
always sees at the entrance ; but ifthese are removed the opening of the hole
will be found clean and splinterless.
The insect bores but two or three holes
at a time and after a delay returns to the same spot to renew operations, mean-
while leaving the uppermost hole
unplugged, although those below are
often revisited in the pauses of oviposi- tion to spread more fluid on the other
completed drills. This explains why
the uppermost drill of a series is often found unclosed at the opening, the
insect having perhaps been frightened
away altogether before the entire com-
pletion of her task.
The egg-holes are drilled at an average
of I. I mm. apart and are 0.4 mm. in
diameter at the entrance.
The harder
outer portion of the stem of the rasp-
berry is first bored through almost
vertically but a little downward, while
in the pith the drills incline downward
in a slight curve (just that of the egg), the general trend of the deeper portion
being at angles varying from I 3 5 O to I 70å but averaging about 145@ to the trend of the initial portion.
The eggs are nearly cylindrical, taper-
ing slightly and well rounded at the
ends, both ends alike in this respect,
2.65 mm. long and 0.55 mm. broad,
the top end, occupying a length of two-
fifteenths of the whole, covered with
little crowded papillae which diminish
in size away from the tip, and where
they fade the surface becomes studded
with lozenge shaped depressions 0.017
mm. long and half as wide. When first
laid the eggs are of a uniform very
pale green, but later become brownish
amber or pale brassy, but with a pale
brownish yellow layer at the lower
end. The eggs are extruded cap-end
hindmost.
This insect seems to prefer to eat the
harder parts, the ribs and veins, of
leaves.
BIBLIOGRAPHICAL NOTES.-V.* Smith, J. B. A new elm insect. Zeuxera i>yrina. p.30-31, f. 6.
BY SAMUEL HENSHAW.
Pearson, A. W. and Editor.
The rose beetle
[Macrodactylus subsfinosus] . p. 44-45 . MINOR ENTOMOLOGIC'AL PUBLICATIONS.-
Lintner, J. A.
Late experience with insects
GARDEN AND FOREST, Vol. I11 (18go), con- injurious to orchard and garden.
p.
tains the following notes and articles :- 70-71 a
Smith, J. B.
An enemy [Botis neluntbialis]
* For Nos. 1-IV, see Vol. 6.
to the Egyptian lotus.
p. 88, f. 18-19 .




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