1890.1 
547 
[Packard. 
on the whole rather small and all of the same shape ; those on the 
prothoracic and first abdominal segments are of about the same 
size, and only a little larger than those on the second and third 
segments ; the two dorsal ones on the eighth abdominal segment 
are of the same size as those on the first abdominal segment, but 
are nearer together and with somewhat larger bases. The ninth and 
tenth segments are rather long, with well developed tubercles. The 
supra-anal plate is well developed, being rounded, not so long as 
broad, bearing on the edge eight hairs, of which the two posterior 
ones are bristle-like and black ; near the middle of the plate are two 
black dorsal bristles. The paranal lobes are large and full, each 
bearing an excrementiferous bristle. The anal legs are long and 
slender, being as long as the ninth segment, and are slightly re- 
tractile. The four anterior pairs of abdominal legs bear on the 
planta from sixteen to eighteen crochets. The setae arising from 
the dorsal and lateral tubercles are long and large, and though ap- 
parently tubular, taper, some to a point, while others are slightly 
docked, but they do not, as usual, end in a broad clear tip. But 
along the extreme lower side of the first and second and seventh 
and eighth abdominal segments, is a series of singular battledoor- 
like setae, a pair to each of the segments named, and arising from 
the lowest tubercle on the side of the segment. These battledoor 
hairs, which are modified secretory setae, are very short, only from 
one-third to one-half as long as the other setae, and have a slender 
pedicel enlarging into an elongate bulbous expansion, the surface 
of which is striated or wrinkled longitudinally, while the tip ap- 
pears under a half-inch objective to be clear. There is also a pair 
of remarkable foliaceous oval appendages at the end of the thorac- 
ic legs, which we have not seen in the few other larvae whose feet 
we have specially examined. These are described and figured in 
our succeeding paper on the External Structure of Caterpillars. 1 
The colors being well preserved in the alcoholic specimens ex- 
amined may be described, in the absence of the living. The head 
is amber mixed with resinous. The body is whitish above ; the tu- 
bercles and their bases pale straw-yellow, as are the anal region and 
•anal legs ; the setae are brownish and there are pinkish stains at 
the base of the prothoracic, and first and eighth abdominal dorsal 
tubercles. Hence it seems that in the first stage of this species the 
mode of coloration of the final stage (5) is already indicated. 
1 These Proceedings, xxv, 1890. 
