Article beginning on page 351.
Psyche 5:351-352, 1888.

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PSYCHE.
THE LIFE-HISTORY OF SEIRARCTIA ECHO.
BY ALPHEUS SPRING PACKARD, PROVIDENCE, R. I. In Entomologica Americana for Au-
gust, 1889 (vol. 5, p. I 53-155), Mrs. An- nie Tr~~mbull Slosson gives an interesting account of the occurrence of Seirarctia
echo Abb. and Sm. in Florida, notes its
habits and adds a description of the
fully grown caterpillar, prepared by
Mr. H. Edwards, She kindly sent me
the eggs from Ormond, Fla., on the eve
of my departure to Europe for the sum-
mer. These Mr. Joseph Bridgham
kindly raised for me, and made excel-
lent enlarged colored sketches of the
larva in its different stages. As these
are evidently faithful studies, and as
Mr. Bridgham has drawn under my
direction the early stages of other arc- tians, I think it will be safe to describe them from his drawings, although un-
fortunately none of the caterpillars were preserved in alcohol. The eggs are
laid in Florida on the dwarf palmetto
(Sabal $almetto) ; my specimens were
fed on lettuce.
Stage &Length 24-3 mm.. Head
nearly as wide as the thickest part of the body, being but slightly narrower than
the prothoracic segment; in tint, dark
brown, rather darker than the body;
rounded. Body of the same thickness
from the 1st thoracic to the 8th abdom-
inal segment. A transversely sublimate
dorsal plate or rudimentary "conical
shield" on the prothoracic segment bear- ing on the front edge a slightly curved
row of six moderately large piliferous
warts ; behind which is a tranverse row
of smaller ones ; the spinulate hairs
arising from the larger warts are very
long and project over the head. Behind
this plate on each side is a single pilifer- ous wart; farther down in front are two
adjoining warts, and still farther down is another group of two similar warts.
The warts on the meso -and metatho-
racic segments are similar in shape, size and position. On each side of each
segment is a group of three large warts, two of them coalesced, the third one he- low the others. On abdominal seg-
ments 1-8 there are two rows of small
dorsal warts, two to each segment, which are not present on the thoracic seg-
ments. The arrangement of the sub-
dorsal warts is the reverse of that of the two hinder thoracic segments ; of the
two sets of warts on each segment, the
upper or dorsal is a single large one,
and the two coalesced ones below are
in the same position as the lower single one of the 2d and 3d thoracic segments.
Lower down are three lateral rows of




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352 ps2'"cHE. [June 1890.
piliferous warts, tliere being three warts on each segment ; those of the upper-
most row (each situated behind a spir-
acle) are the largest and arranged ob-
liquely ; those of the middle row are
crescent-shaped ; while those of the
third row are minute and situated at the base of the legs, or in corresponding
places on the apodal segments. It is to
be observed that the arrangement of
the warts on the 8th segment is exactly
the same as on the seven segments in
front of it. On the 9th segment there
are two large subdorsal groups of three
coalesced segments, the area either one
of them occupies being the same as that
covered by one of the double warts on
the 2d or 3d thoracic segments.
The
suranal plate is roughened with crowded
warts. The body is pale vandyke
brown, the warts darker. The hairs
are nearly twice as long as the body is
thick, being long and sparse.
Stage II.-Length 4-5 mm. The
head is a little smaller than before, but the body is of the same shape ; the
warts on the protl~oracic shield are less pronounced, and the warts on the rest
of the body preserve the same arrange-
ment as before, but are decidedly small- er. The body is slightly more reddish
in tint.
Stage III.- Length 7 mm. The
head is now slightly narrower in pro-
portion to the width of the body than
before. There is now a great change
in the nature of the piliferous warts,
and a marked increase in the number
of hairs. The prothoracic shield shows
a tendency to divide into halves.
The
primary piliferous warts have under-
gone a differentiation so that the sur-
face has become covered with small
secondary piliferous warts each bearing
a hair one-half shorter than those of the preceding stages, so that the longest
ones are about as long as the body is
thick ; the hairs are thus assanged in
thin tufts 01- verticils. The two com-
pound warts on the 9th abdominal seg-
ment are larger than before. The arc-
tian features thus seem to be assumed
in the third stage.
Stage IV.-Length 10-11 mm. The
head is slightly smaller in proportion
than before and now differs much in
mode of coloration; there is a medi-
an pale stripe from the the vertex to the front ; the clypeus being pale, and con- necting with a broad lateral pale band.
The prothoracic shield is now com-
pletely divided by a median line. The
piliferous warts are somewhat smaller
than before, but the hairs are of the
same length. The position of the dor-
sal warts on the 2d and 3d thoracic
segments have somewhat changed their
-
position besides being smaller. They
are arranged in a slightly curved line
across the segment. The four dorsal
ones on abdominal segments 1-8 are
arranged more in a trapezoid than be-
fore. The two dorsal warts on the 9th
segment are now about half as large as
in the preceding stage. The general
color of the body is more reddish than
before, with a slight chestnut tint.
Stage V. - Length 15-16 mm.
(Evidently underfed.), The head is
marked as before, but the body is




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June ~Sgo.] p3'2TfiZ'. 353
considerably thicker. The markings
of the body have materially changed.
The prothoracic shield, in the two
last stages bplit in two longitudinally, is now also split tranversely, so that .it is represented by four transversely narrow
piliferous warts. On each succeeding
segment there is a transverse dorsal
broad black-brown band, which en-
closes a yellowish white narrow stripe,
which in the middle and at each end
enlarges into a round spot; there are
ten such curious whitish stripes on a
blackish ground, which only extend
part way down the sides of the body
toward the spiracles. The piliferous
warts are not so pronounced as in the
preceding stages, while the body and
hairs are of a pale chestnut hue.
Stage VI and last.-Length
23-24 mm. (Evidently underfed, Mr.
Edwards's specimens measuring 52
mm.). In the final stage the head
is pale chestnut, with no black poi--
tion. The top of the body is now
black, and each segment except
the first behind the head bears two
transverse white stripes, one in front
and the other behind a transverse
chestnut-red band, enclosing the pilifer- ous warts, which are much more prorni-
nent than in the 5th stage. Of the two
yellowish white transverse stripes, the
one on the front of the segment is divided into a central dot with a separate slash on each side ; the hinder band consists
of three portions, a central dot, from
which a stripe passes each side, and in- stead of ending in a dot, makes a loop
or hook. Our drawings made by Mr.
Bridghain agree well with Mr. Ed-
wards's description.
It thus appears that the markings
of the two last stages of this larva are very different from those of any genus
whose larval history is known to us ;
Mr. Edwards has pointed out its rela-
tions to the larva of Arachnis and
Ecpantheria, with which we are not
familiar.
TWO SPECIES OF AESCHNA.
BY HERMANN AUGUST HAGEN, CAMBRIDGE, MASS. I. AESCHNA SITCHENSIS.
Aeschna sitchensis Hagen, Syn.
Neur. N. A. I 19, I.
Blackish-brown, spotted with blue ;
head yellow in front, anteriorly with a
narrow transverse black line ; superiorly a large black spot in the shape of a T,
nearly or entirely connected each side
with a black band before the eyes, form- ing two yellow spots surrounded with
black on the superior part of the front ; rhinarium and border of the labrum
black ; eyes largely connected ; occiput .yellow, hind border elevated, black on
each side ; thorax fuscous, dorsum with
two median elongated points ; sides




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