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Psyche 
[Vol. 90 
the time the cocoon was spun. Most of the pellets were incorporated 
into the cocoon. 
Cocoon Spinning. Before fecal pellets were spun together a web- 
like matrix was laid down on the walls. The larva pressed its salivary 
lips onto various points of the walls and partitions and deposited a 
small droplet of material from which a short strand of silk was 
pulled and anchored elsewhere. The apical partition was covered 
with many more strands than the walls or basal partition. Most of 
the strands were attached anteriorly to the apical partition which 
was also that portion of the cell where most of the fecal pellets had 
been deposited. The larva anchored a pellet by holding it with the 
mandibles, depositing a small drop of material with the mouth, 
pulling away and attaching the other end to another pellet, leaf hair 
or portion of the wall. As the salivary component was daubed onto 
various structures by the salivary lips, the labium appeared to be 
split so that the silk was pulled through as if being threaded, and a 
steady pressure was maintained. The fecal pellets were spread evenly 
across the anterior portion of the cell and when all were anchored a 
cavity lined by white threads covering the entire cell had been 
formed. During this time the larva showed much mobility and agil- 
ity, moving freely about the cell and turning completely around 
several times as necessary. 
Once the fecal pellets were spun together more tiny strands were 
laid down within the cavity until a fairly dense network of threads 
that would be the template for the cocoon was formed. The cocoon 
was composed of one thin transparent and cellophane-like layer. 
The larva deposited the layer in one of two ways. Either a single 
thread was grasped with the mandibles and a clear liquid was 
exuded as the head moved up and down the strand or the mandibles 
separated 2 or more strands, depositing the liquid between them, 
moving the head back and forth until the layer dried. A few fecal 
pellets were incorporated into the matrix and flattened and spread 
out. No recognizable nipple was formed anteriorly. Instead, an area 
somewhat more transparent and of similar thickness to the rest of 
the cocoon was formed (Fig. 4). The average time from initiation of 
cocoon spinning to completed cocoon was 3.7 days (Table 1). 
Pupation and Adult Emergence, On 27 July 1981, 10 overwinter- 
ing larvae were placed in an incubator at 30° C in order to observe 
