Guide to the study of insects, and a treatise on those injurious and beneficial to crops: for the use of colleges, farm-schools, and agriculturists online

eight days. It remains thirteen days in the ground, being



220



HYMENOPTERA.



most of the time in the pupa state, while the fly lives nine days.
The first brood of worms appeared May 21, the second brood
June 25. Winchell describes the larva as being pale-green,
with the head, tail and feet, black, with numerous black spots
regularly arranged around the body, from which arise two or
more hairs. Figure 146, 1, shows the eggs deposited along the
under side of the midribs of the leaf; 2, the holes bored by the
very young larvae, and 3, those eaten by the larger worms.

In transporting gooseberry and currant bushes, Walsh recom-
mends that the roots be carefully cleansed of dirt, so that the

cocoons may not be car-
ried about from one gar-
den to another. The leaves
of the bushes should be
examined during the last
week of May, and as only
a few leaves are affected
at first, these can be de-
tected by the presence of
the eggs and the little
round holes in them, and
should be plucked off and
burnt. The female saw-
fly is bright honey-yellow,
146 - with the head black, but

yellow below the insertion of the antennae. The male differs
in its black thorax, and the antennae are paler reddish than in
the female.*

The genus Empliytus has nine-jointed antennae ; the third

* Mr. Norton has communicated the following description of the larva of another
saw-fly of this genus which infests the weeping-willoAv.

" Nematus trilineatus Norton. The larvas of this were first seen upon the weep-
ing-willows about August 1st, in immense numbers, almost wholly stripping large
trees of their leaves. They begin upon the edge of the leaf and cat all of it except
the inner midrib. They are very sensitive to disturbances, very lively, and are
generally found with the hinder part of their bodies bent up over the back. They
are twenty-footed, of a bright green color, palest at head and tail, with five rows of
black dots down the back, the outer row upon each side irregular and with inter-
vals. On each side above the feet is another row of larger black dots, and the three
anterior pair of feet ai-e black at the base, middle and tip.

" A great number of the saw-flies were found flying about the trees, August 19th,
in the proportion of about ten males to one female. The males being almost
wholly black upon the thorax."




TEXTHREDINIIU-:.



221



and fourth joints of equal length; the wings have two subcos-
tal Miid three median cells, the first as long as the second, gen-
erally longer ; the first receiving one recurrent vein, the second
two. Wr have found the larva of E. maculatus Norton on the
cultivated strawberry, to which, in the Western States, it some-
times does considerable damage, but it can be quite readily
exterminated by hand-picking. Mr. Riley has carefully ob-
served the habits of this insect, and we condense the follow-
ing remarks from his account in the Prairie Farmer: Early in
May, in Northern Illinois, the female saw-fly deposits her eggs
in the stem of the plant. They are white and .03 of an inch
long, and may be readily perceived upon splitting the stalk ;
though the outside
orifice, at which
they were intro-
duced, is scarcely
perceptible, their
presence causes a
swelling in the
stalk. By the mid-
dle of May the
worms will have
eaten innumerable
small holes in the
leaves. They are
dirty yellow and Fi s- 147 -

gray green, and at rest curl the abdomen up spirally. They
moult four times, and are, when full-fed, about three-fourths of
an inch in length. They make a loose, earthen cocoon in the
ground, and change to perfect flies by the end of June and
the beginning of July. A second brood of worms appear,
"and in the early part of August descend into the ground and
remain in the larva state until the middle of the , succeeding
April, when they finish their transformations. The fry is pitchy
black, with two rows of dull, dirty white, transverse spots upon
the abdomen. The nine-jointed antennae are black, and the
legs are brown, and almost white at the joints. Fig. 147 rep-
resents the Strawberry Emphytus in all its stages of growth.
1, 2, ventral and side-view of the pupa; 3, the fly enlarged ;




222 HYMENOPTERA.

5, the same, natural size ; 8, an antenna enlarged ; 4, the
larva while feeding ; 6, the same, at rest ; 7, the cocoon ; 9, an
egg enlarged.

Of the genus Dolerus, known by the second submarginal cell
receiving two recurrents, D. arvensis Say, is a common blue-
black species found in April and May on willows.

The genus Selandria is the most injurious genus of the
family. It embraces the Pear and Rose-slugs, the Vine-slug
and the Raspberry slug. The flies are small,
black, with short and stout nine-jointed an-
tennae, and broad thin wings. "The larvae
are twenty and twentj^-two-footed, present-
ing great differences in appearance and habit,
being slimy, hairy or woolly, feeding in
companies or alone, eating the whole leaf as
they go, or, removing only the cuticle of the
leaf, and forming sometimes one and some-
times two broods in a year. Selandria vitis,
the Vine-slug, is twenty-footed ; it has a
smooth skin, and the body is somewhat thick-
ened in the middle but slender towards the
tail. "While growing, the color is green
above, with black dots across each ring, and
yellow beneath, with head and tail black.
They live upon the vine and are very destruc-
tive, feeding early in August in companies, on
rig. 148. ^ ne i ower side of the leaf, and eating it all as
they go from the edge inwards. There are two broods in a
season. The fly is shining black, with red shoulders, and
the front wings are clouded." (Norton.)

S. rubi Harris feeds on the raspberry, appearing in May.
The larva is green, not slinry, and feeds in the night, or early
in the morning. S. tilice feeds on the linden. The Pear-slug, S.
cerasi Peck (Fig. 148, larvae feeding on a leaf of the pear, and
showing the surface eaten off in patches ; a, enlarged ; 6, fly),
is twenty-footed ; it narrows rapidly behind the swollen thorax,
and is covered with a sticky olive-colored slime. It feeds on
the upper side of the leaves of both the wild and cultivated
cherry and pear trees, and has been found on the plum and





TENTIIREDIXIDyE. 223

mountain-ash. It appears in June and September. The fry is
shiny black, with the tips of the four anterior femora, and the
tibice and tarsi, dull white. An egg-parasite, belonging to the
genus Encyrtns, renders, according to Peck, a great number
of its eggs abortive.

The Rose-slug, Selandria rosce Harris, is longer than the Pear-
slug, the body being scarcely thickened anteriorly, and not
covered with slime. It is pale-green and yellowish beneath.
It appears in July and August, and does great injury in dis-
figuring and killing the leaves of the
rose, which remain dried and with-
ered on the bush. When full-fed,
the larva, like the Pear-slug, makes
a cocoon beneath the surface of the
ground. The flies are seen in abund-
ance about the rose-bushes as soon F1 s-
as the leaves are expanded, when they may be caught with
nets, or the hand on cloudy days. Hand-picking, and the
application of a very weak solution of carbolic acid, coal oil,
whale oil soap, or quassia, are useful in killing the larvae.

On the 25th of July a young friend brought me a large num-
ber of some remarkable larvae (Fig. 149, natural size) of a
saw-fly, which I surmised might belong to this genus. It pre-
sented the appearance of an animated, white, cottony mass,
about an inch long and two-thirds as high. The head of the
larva is rounded, pale whitish, and covered -with a snow-white

powdery secretion, with prominent
black eyes. The body (Fig. 150,
naked larva) is cylindrical, with eight
rig. 150. pairs of abdominal legs, the segments

transversely wrinkled, pale pea-green, with a powdery secre-
tion low down on the sides, but above and on the back, arise
long, flattened masses of flocculent matter (exactly resembling
that produced by the woolly plant-lice and other Homopterous
Hemiptera) forming an irregular dense cottony mass, reaching
to a height equal to two- thirds the length of the worm, and con-
cealing the head and tail. On the 27th and 28th of July the
larvae moulted, leaving the cast skins on the leaf. The} r were
then naked, a little thicker than before, of a pale-green color,




224



HYMENOPTERA.




Fig. 151.



and were curled on the leaf. They eat out the edge of the
leaf x)f the butternut tree. Sometime during August, two

cocoons were spun between the
leaves, but I did not succeed in
raising the saw-fly. On describing
the larva, in a letter to Mr. E. Nor-
ton, he kindly sent me alcoholic
specimens of larvae (without the
woolly substance, which dissolves
and disappears in alcohol) found
feeding on the hickor}', which are
apparently, from the comparison of
alcoholic specimens, identical with the Butternut Selandria.
The adult fiy (Fig. 151, cf, , cocoon), he has named S. caryce,
of which he has kindly furnished
me with the subjoined description. *
Allantus is closely related to Se-
landria, both in its structure and its
habits, but differs in having the an-
tennae short and somewhat clavate.
A. basilaris Say is a common species.

The Pine saw-fly, Lopliyrus, may be known by the feathered
antennae of the male. L. abietis Harris (Fig. 152, female)
infests the fir and pitch-pine. The male is black above and
brown beneath, while the female is yellowish brown above,

* Selandria caryce Norton, nov. sp. (Belonging to tribe 2. Under wings with one
middle cell. Div. A. Antennae filiform, short).

Female. Color shining black. The pro- and mesothorax and scutellum rufous,
the apex of the latter black ; the nasus and legs white, with their tarsi blackish ; the
base of coxas and a line down the upper side of the legs black. Antennae short,
the second joint as long as the first; the four final joints together, not longer than
the two preceding. Nasus slightly incurved. Claws of tarsi apparently bifid,
Wings subviolaceous. Lanceolate cell petiolate, the first submedial cell above it,
with a distinct cross vein. Under wings with one submarginal middle cell (all
other species have this cell discoidal), the marginal cell with a cross nervure, and
all the outer cells closed by an outer nervure, which does not touch the margin.
The submedial cell extended nearly to margin. Length, .25 of an inch. Expanse
of wings .40 of an inch.

" The male resembles the female, but the under wings are without middle cells.
The larvae feed upon the leaves of the hickory (Juglans squamosa.) They are
found upon the lower side of the leaf, sometimes fifteen or twenty upon one leaf,
which they eat from the outer extremity inward, often leaving nothing but the
strong midribs. They cover themselves wholly with white flocculent tufts which
are rubbed off on being touched, leaving a green twenty-two legged worm, about .75




Fig. 152.



TENTHREDINID2E.



225




with a sliort black stripe on each side of the thorax. The
hr\:v :ire about half an inch long, of a pale dirty green, yel-
lowish beneath, striped with green, and when full-fed yellowish
all over. They are social, and may often be found in consider-
able numbers on a single needle of the pitch-pine. The larva;
spin tough cocoons
among the leaves,
and the flies appear
during August, but
probably in greater
n umbers in the
spring.

These slugs can
be best destroyed
by showering them
with a solution of



carbolic acid, pe-
troleum, whale oil Fig. 153.
soap, or tobacco water. Mr. Fish has sent me the larvae of a
saw-fly, allied to L. abietis, which, in Eastham, Mass., ravaged
the young pitch-pines planted in the sandy soil of that region.*
The eggs arc laid singly in the side of a needle of the pine ;
though sometimes an egg is inserted on each side of the
leaf.

Mr. Riley has described the habits of the White-pine saw-fly,

of an inch in length when fully grown ; darkest above, and with indistinct black-
ish spots upon the sides. The head i - white with a small black dot upon each side.

" Specimens were taken upon the leaves July 4th. Went into the ground about
the 20th of July. The cocoon is formed near rhe surface of the ground of a little
earth or sand drawn together. Four specimens came forth about August 22d, all
seeming very small for so large larvae."

*Ou sending specimens of the male and female to Mr. Norton ho writes that
this is an undeseribed species, of which ho has prepared the following description :

" Lophynujrintu-rifftdaJXorton. New Species. Female. Length, 0.30; expanse
of wings, (>.(;.> of an inch; antennae seventeon-jointod, short, brown: color, luteous
brown, with a black line joining the ocelli, a bla-k stripe down each of the three lobes
of the thorax above, and the sutures behind; body paler beneath ; the trochantors
and base of (he; tibia? waxen; claws with an inner tooth near the middle; wings
\ \ liulitly clouded; cross nervure of the lanceolate cell straight. Male. Length,
cpaate <>r wings, o.r>.~> of an inch; antenna? fifteen -join ted, black, quite sliort,
with twelve branches on each side, those at the base nearly as long as t'ic -i\th
and seventh; apical joint simple, enlarged at base; color of insert black, with the
abdomen at apex and beneath yellow-brown; legs the same color at base; below
the knees whitis-h.

15



226



HYMENOPTEKA.



L. Abbotii Leach. The flies appear early in June, and there is
but a single brood of larvae, which remain on the trees, in Illi-
nois, until November, and hibernate before changing to pupae.
The female is honey-yellow, with pale rufous legs, and the
male is jet black. Fig. 153 represents, after Riley, the trans-
formations of this species, whose habits closely resemble those
of L. abietis. 1, is the fly somewhat magnified; 6, magnified
antenna of the male ; 7, female antenna ; 2 and 3, pupae ;
4, larvae in different positions, natural size ; 5, cocoon. The L.
Lecontei Fitch has been found feeding on the Scotch and Aus-
trian pines in New Jersey, and has been described by Mr.
Riley. The larva is an inch long, dirty or yellowish white,
with dorsal black marks wider before than behind, and usually
broken transversely in the full-grown individuals ; they are
farther apart than in L. Abbotii. "The lateral spots are some-
what square, with an additional row of smaller black marks
below them, and the last segment is entirely black above. The
antennae of the male fly are twenty-one-jointed, and have on
one side seventeen large, and on the other seventeen small
branches, there being eighteen on one side and fifteen on the
other in L. Abbotii. The female may at once be distinguished
from L. Abbotii by her abdomen being jet-black above, with a
small brown patch at the end, and a transverse line of the
same color just below the thorax."

There are several allied genera, such as Cladius (C. isomera
Harris), Lyda (L. scripta Say), and Xyela (X. infuscata Har-
ris), which belong here. The last genus, Cephus, which by some



" The females of Lophyrus are all much alike and I have found the number and
forms of the joints of the antennae, so far, the only reliable guide. The male looks
precisely like that of L. abietis,\mt the form of the antennas differs in being much
shorter. The female looks much like L. abdominalis Say, taken on the pine near
New York. The following list will show how the species may be distinguished by
counting the number of joints."



L. Fabricii Leach,
L. compar Leach,
L. pinus-rigida Norton,
L. Abbotii Leach,
L. abietis Harris,
L. abdominalis Say,
L. pinetum Norton,
L. Americanus Leach,
L. insularis Cresson,
L. Lecoutei Fitch,



male, not described, female, 16 joints.







16






15 joints


17






not described


17






21 joints,


18






not described,


18






19 joints,


18






not described,


19






17 joints,


20






17 "


21





Pine.



Pine.



Pine.



UROCERIDJE. 227

authors is placed in the next family, is retained by Norton in the
present group. The larva is, in Europe, injurious to rye and
\vheal , boring in the stems of the plant. Ceplius abbreviatus Say
is our more typical form, though rarely met with. C. trimaculatus
Say is found in New York early in June, according to Dr. Fitch.

UROCERID^E Leach. The family of "Horntails" are so-called
from the long prominent horn on the abdomen of the males,
while the ovipositor or "saw," resembling that of the true saw-
flies, is attached to the middle of the abdomen, and extends far
beyond its tip. They are of large size, with a long cylindrical
body and a large head, square next the thorax, but much
rounded in front. The antennae are long and filiform. The
l;n-\;e are "cylindrical fleshy grubs, of a whitish color, with a
small rounded horny head, and a pointed horny tail. They have
six very small legs under the fore-part of the body, and are pro-
vided with strong and powerful jaws, wherewith they bore long
holes in the trunks of the trees they inhabit. Like other borers
these grubs are wood-eaters, and often do great damage to pines
and firs, wherein they are most commonly found." Harris
farther states that, when about to transform, the larvae make
thin cocoons of silk in their burrows, interwoven with little
chips made by the larva. "After the chrysalis skin is cast off,
the winged insect breaks through its cocoon, creeps to the
mouth of its burrow, and gnaws through the covering of bark
over it, so as to come out of the tree into the open air."

XiL>]ti<lria is so-called from the sword-like ovipositor, which
is much shorter than in the succeeding genera. The body is a
little flattened, somewhat turned up behind, and the tip of the
abdomen ends in an obtuse point, while the antennae are short,
curved and tapering at the end. Xiphidria albicornis Harris is
black with yellowish legs and white antennae, with the two
lowest joints black. It is nearly three-fourths of an inch long.

The typical genus of the family is Urocerus, which has a large
body, with a large ovipositor and long, sixteen to twenty-four-
jointed antennae, while the body of the male ends in a stout
acute horn. U. albicornis Fabricius has white antennae, and the
female is of a deep blue-black color, while the male is black.
It is found on pine trees in July. It is an inch in length.



228 HYMENOPTERA.

The genus Tremex is known by the wings having two mar-
ginal and three submarginal cells. Tremex Columba Linn, in-
fests the, elm, pear and button-wood. The female is an inch
and a half long, rust-red, varied with black, while the abdomen
is black with seven ochre-yellow bands on the upper side, all
but the two basal ones being interrupted in the middle. They
fly during the last of summer.

"Dr. Harris thus describes the habits of this interesting in-
sect. The female, when about to lay her eggs, draws her borer
out of its sheath, till it stands perpendicularly under the middle
of her body, when she plunges it, by repeated wiggling motions,
through the bark into the wood. When the hole is made deep
enough, she then drops an egg therein, conducting it to the
place by means of the two furrowed pieces of the sheath. The
borer often pierces the bark and wood to the depth of half an

inch or more, and is sometimes driven
in so tightly that the insect cannot
draw it out again, but remains fast-
ened to the tree till she dies. The
eggs are oblong oval, pointed at
each end, and rather less than one-
twentieth of an inch in length.
Fig - 154< "The larva, or grub, is yellowish

white, of a cylindrical shape, rounded behind, with a conical,
horny point on the upper part of the hinder extremity, and it
grows to the length of about an inch and a half. It is often
destroyed by the maggots of two kinds of Ichneumon-flies
(Rhyssa atrata and lunator of Fabricius). These flies may
frequently be seen thrusting their slender borers, measuring
from three to four inches in length, into the trunks of trees
inhabited by the grubs of the Tremex, and by other wood-eat-
ing insects ; and like the female of the Tremex they some-
times become fastened to the trees, and die without being able
to draw their borers out again."

We have noticed the trunk of an elm, at Saratoga Springs,
perforated by great numbers of holes, apparently made b}^ these
insects. T. latitarsus Cresson (Fig. 154 ; a, antenna ; 6, wing ;
c, hind leg) is remarkable for the expansions on the hind legs.
It lives in Cuba.




LEPIDOFTERA.



LEPIDOPTERA.

BUTTERFLIES AND MOTHS are readily recognized by their
cylindrical, compact bodies ; their small head, with its large
clypeus ; by the maxillae being prolonged into a tubular





Fig. 155.* Fig. 156.

1 * tongue;" the obsolete mandibles; and the' broad, regularly
veined wings, which are covered with minute scales.

Their transformations are complete ; the active larvae assum-
ing a cylindrical, worm-like form, being rarely footless, and



am



ab




uid
Fig. 157. Fig. 158.

having from one to five pairs of fleshy abdominal legs, besides

the three pairs of corneous jointed thoracic limbs. A large

proportion (butterflies excepted) spin silken cocoons before

*For explanation of cuts, 155 to 171, see pages 233 and 234.



230



LEPIDOPTEEA.



changing to pupae (chrysalids, nymphs). In the pupa state
the limbs and appendages of the head are soldered together,
and the head and thorax tend to form one region, upon which
the third region, or abdomen, is more or less movable. Three




lb

Fig. 159. Fig. 160. Fig. 161.

or four genera of the lower families are partially aquatic, while,
as a whole, the suborder is purely terrestrial.

The three regions of the body are very distinct, but the head,
though free, is smaller and with its parts less equally developed





Fig. 162.

than in the Hymenoptera, and the "propodeum" has now be-
come plainly the first abdominal ring. The abdomen is also
longer, with the genital armor partially exserted, thus showing
a tendency to decephalization. In fine, the whole body is




Fig. 163. Fig. 164.

loosened and less compact than in the Hymenoptera. Their
broad wings ; obsolete mouth-parts, with the abnormally devel-
oped maxillae ; and active larvae, with their worm-like shape,



LEPIDOPTERA.



231



..-o




Fig. 165.



are also characters which show that they are more degraded than
the lIyiiH'iioptc:a. There is also a greater disproportion in the
relative size of the three thoracic rings. In the abdominal rings
the pleuritcs are much larger than in Hymenoptera, where they
arc partially obsolete. They
scarcely use the legs, the fore
pair (so remarkably differen-
tiated in the higher Hymenop-
tera) being partially obsolete
in some butterflies (Vanessa,
etc.). They are essentially
fliers, not having the great
variety in the mode of loco-
motion observable in the Hymenoptera. No parasites are
known to occur in this suborder. They are only social while in
the larval state, and then merely because their eggs, in such in-
stances, are laid in bunches, and on distinct food-plants to
which the larvae are confined. The adults rarely
take an active part in the economy of nature,
and have but little opportunity for the mani-
festation of instinct and reason, though the
larvae in seeking for suitable places in which
to undergo their transformations often exhibit
Fig. ice. wonderful instinct.

The readiest method of determining the natural position of
groups is by a comparison of their degradational forms. Thus
we find that in the degraded Hymenoptera the tripartite form
of the body is preserved ; while, on the contrary, in the wing-
less Lepidoptera (such as the female
of Orgyia and Anisopteryx) the body
is either oval, the head being less
free and smaller than in the winged
form, and the thorax and abdomen
continuous, their respective rings
being of much the same size and
shape, while the legs are feeble:
or, as in the female of (Eketicus,
the body is elongated, and worm-like.





Fig. 167.

The wingless moths,



then, are much lower than the worker ants, the female Scolia,



232



LEPIDOPTERA.



etc., giving us an unfailing test of the difference in rank of the
two suborders. In their habits and transformations, and

in their external
anatomy, the Lep-
idoptera vary less
than other insects.
The Lepidop-
tera, while in the
perfect state, can
be scarcely said to
walk much, com-
pared with beetles
and other walking
insects, the legs being only used to support them while at rest,
and not for locomotion. They move almost entirely by their
broad wings, which