1988] 
Deyrup, Cronin, & Kurczewski — Alio chares 
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structed section of cocoon. After completing a loop, the larva rears 
back its head drawing out two threads, then attenuates the threads, 
and breaks them with a movement of the head. The head is lowered 
and another loop initiated at the base of the hairs (Figs. 6A&B). 
The larva works steadily with stereotypic motions. If disturbed, the 
larva draws its head into the finished part of the cocoon; when no 
longer alarmed, it raises its head, repeatedly touching the side of the 
cocoon until it reaches the rim, whereupon it begins to make loops 
and hairs as before. The shape of the outer cocoon is determined by 
the reach of the larva, and is larger and rounder than the finished 
cocoon. When the opaque inner cocoon is constructed, it draws 
together the outer cocoon to make it narrower and more compact. 
The larva requires about 48 hours to complete its cocoon. 
The function of the hairs is unclear. They might lodge the cocoon 
even more securely in the web, but the numerous threads holding 
the posterior end of the cocoon in place appear adequate for this 
purpose. It seems likely that the hairs have a defensive function. It 
might be easier to guess the function of the hairs if we knew what 
potential enemies were present in natural habitats such as deep bark 
fissures and piles of rocks. Zatypota nigriceps (Walsh) is an ichneu- 
monid with habits similar to those of A. azureus: it lives as an 
external parasitoid on spiders in their webs, and the cocoon is sus- 
pended in the web. The cocoon of this species is covered with erect 
loops (Townes and Townes 1960). We reared a larva of Z. crassipes 
Townes at the Archbold Biological Station; this specimen produced 
a cocoon covered with loops that were more or less appressed, but 
still provided a loose covering over the entire cocoon. The cocoons 
of both Allochares and Zatypotus are completely exposed to small 
parasitoids that could evade the strands of the spider web. It seems 
likely that the hairs and loops on these cocoons may offer some 
protection from small generalist parasitoids that attack exposed 
cocoons, such as the widespread pteromalid Dibrachys cavus 
(Walker). Studies of crop plants show that a dense pile of erect hairs 
is a general defense against sap sucking insects (Levin 1973) as well 
as some parasitoids and predators of these insects (Schuster and 
Calderon 1986). The same physical principles should apply to the 
cocoon of Allochares. 
The color of A. azureus cocoons collected outdoors is medium to 
dark brown. The cocoons produced in the laboratory were white 
