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Psyche 
[Vol. 93 
the new (pupal) shape, the head capsule moved smoothly posteriorly 
along the center line of the animal’s ventral surface. The capsule 
paused briefly when it reached the “collar” or the anterior end of the 
band of silk that fastened the larva to the pupal line, then moved on 
smoothly, passing beneath the mat of silk threads holding the larva 
to the pupal line. As the head capsule neared the posterior end of the 
body, the cuticle there began to wrinkle during each contraction of 
the animal’s body, also as noted previously (Eberhard 1970). When 
the posterior end of the pupa broke free from the remains of the 
larva, the head capsule was left as part of the mass of larval material 
that remained attached to the line. Careful dissections of some of 
these masses in water revealed the presence of not only the head 
capsule but also a long tubular sheath of very thin, transparent 
cuticle that bore the rows of dark denticles found near segmental 
boundaries on the ventral surfaces of larvae (Eberhard 1970). Thus 
the entire larval cuticle was shed during pupation, and the head 
capsule was not engulfed. 
With respect to point 2 (posterior segments of larval body dis- 
carded during pupation), the new evidence does not clearly contra- 
dict previous descriptions. Several minutes prior to the migration of 
the head capsule to the posterior end of the larva, the last two and 
one half segments of the larva’s body had darkened to a caramel 
brown color, and the material inside was amorphous and inert 
when viewed through the larval cuticle. In contrast, there were clear 
internal movements of well defined structures just anterior to this 
area, and it appeared that the posterior tip of the pupa had already 
formed and was being repeatedly pushed posteriorly against the 
inert brown material. When the larval cuticle was finally discarded 
(above), these posterior two and one half segments did not wrinkle 
or contract as did the rest of the larval cuticle, but retained their 
form, and the rows of denticles marking the segmental boundaries 
on their ventral surface remained clearly visible and as far apart as 
they had been in the intact larva. 
Discussion 
Probably the pupation process in the Leptomorphus species of 
previous reports was the same as that described here. The larval 
head capsule is small and partially transparent, and difficult to see 
without magnification. The observations of larval head capsules on 
