MEMOIES OF THE jSTATIOXAL ACADEMY OF SCIENCES. 
281 
very opaque, tracheal liue evident. As the stage advances humps appear slightly on all the 
intervening segments and the larva more nearly resembles the last stage. 
Stafje IV . — Head higher than wide, narrowing to vertex, flattened in front; green, the clypeus 
shining, a black line as before; width, 2.1 mm. Dorsal processes as in the mature larva, but much 
slighter; present on segments 5 to 12 and a slight one on 13, consisting of two small tubercles. 
The processes are all small, except on segments G and 12, Markings as before, but more distinct 
and approaching the mature larva. All the mature characters are now assumed, but are less 
developed than in the next, which is the last stage (Stage V). (Dyar MS.) 
Stage Y. — The following description v'as drawn up October 5, from the three specimens figured 
on PI. XXIII. They were kindly sent me by Jliss IMary Murtfeldt, from Kirkwood, Mo. 
Length, 32-33 mm. Body much compressed. Head moderately large, rather narrow and 
high, slightly bilobed above, not so wide as the body; pale green, with four broad white bauds in 
front and on the side, the two median ones approaching each other over the apex of the clypeus, 
and then separating. Behind, a white hand on each side passes down underneath the back of the 
head, making six white bauds in all. On each side of the front is a narrow, blackish liue, edging 
each lateral frontal line. 
The three thoracic segments of nearly the same size and width, much wrinkled, but unarmed, 
and with three white longitudinal bauds on each side, the lower one narrow, irregular, and edging 
the lateral conspicuous infrastigrnatal pui'plish line. 
Abdominal segments 1 to S with a high recurved, soft, fleshy, distinctly retractile, conical 
tubercle, the apex of which is bilobed and curved over backward so as to touch the apex of a 
second much smaller conical tubercle, the flrst one being a little smaller than the others, and the 
last one a little slenderer than the others. On the tip of each tubercle is a reddish brown median 
line, best marked on the second and third tubercles, the other being simply tipped with the same 
hue. The sides of the tubercles and of the segments bearing them is glaucons-white, and from 
the anterior part of the base of each tubercle a green line passes oblicpiely backward and down- 
ward to the suture behind. There are eight of these lateral oblique lines; the eighth is a little 
higher than the seventh, is piliferous, bearing a short hair on each side. Xiath abdominal segment 
not tiiberculated, but with a pair of small dorsal tubercles, Suraiial plate narrow, quite smooth, 
and witli four longitudinal white bands. Low down on the sides of abdominal segments 7 to 9 is 
a broken infrastigrnatal purplish line which extends along the underside of the rather slender 
anal legs. Sx)iracles yellow, with a dark, narrow edge. Distal ends of the four pairs of middle 
abdominal legs purplish, with two parallel black lines above the plauta. Thoracic legs pale green,, 
with a narrow dark red line on the outside. 
There is not much variation in the three individuals, except that the purplish lateral line in 
one is represented ou the abdominal segments by isolated spots. The tubercles are unusually 
extensile and flexible in this caterpillar, and their resemblance to the serrate edge of the elm 
leaves, together with the leal-green ground color and greenish white markings, and purplish 
brown spots like those on the elm leaves, is most remarkable. 
Habits . — The larva eats away the leaf from the midrib, leaving the latter as a perch,” on 
M'hich it rests just like Lophodouta. Wlieu large the larva rests ou the base of the leaf or stem,. 
(Dyar.) 
FULLY GROAVN LABVA OF IIYPARPAX AURORA (see p. 186). 
Last stage ( Y). — ^Like Stage lY at flrst. Later aud gradually the colors change. Head rounded, 
higher than wi<le, not reaching above segment 2 nor retracted within it; width, 3 mm. Ground 
color white with a yellow tint, reticulated with mottled bauds of ])ur]>le-brown, a broad cue 
running from antenine to top of each lobe. Body pointed dorsally. On segments 5 and 12 the 
tubercles i red, large, conspicuous, elsewhere very small, though i ou segments 6-8 are white and 
rather distinct. All other tubercles inconspicuous, setie dark, moderately long. Venter and legs 
purple-brown, dotted with white; sides whitish green, finely dotted with white aud brown and 
shading into a brighter green ou segments 2-4 (rei)resenting the usual patch of Schi/ura aud 
Jauassa). Ou vsegmeuts 2-3 a dorsal purple-brown band, white dotted and bordered with yellow; 
on segment 5 a white subdorsal baud marked Avith fine irregular purple-brown lines, beginning at 
tubercle i, loops uj) to i ou 12 aud runs to anal foot. The dorsal space thus inclosed is bright 
yelloAvish leaf-green, dotted with white, with a narrow white dorsal line indicated. Tubercle i on 
segment 6 is marked by a little white patch, and there is a triangular eiilargemeut of the subdorsal 
