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Psyche 
[Vol. 94 
same egg mass for roughly 15 minutes. One of the females lost 
interest, walked away and later encountered her own eggs on 
another shoot of the same plant. Thus it appears that A. sparsa 
females can home from limited distances and can discriminate 
between their own egg mass and those of their neighbors, behavioral 
capabilities strikingly similar to those described by Tallamy and 
Denno (1981) for the subsocial tingid, Gargaphia solani Heidemann. 
Larval Period 
Grazing pattern 
Larvae begin to graze on the under surface of their natal leaf 
immediately after eclosing from the egg. Young larvae consume the 
lower epidermis and part of the mesophyll leaving the upper epi- 
dermis intact. Later instars consume the entire leaf, save the central 
midrib. First instar larvae advance slowly in an organized front on 
their natal leaf, grazing a path along one side toward the tip and 
then back toward the petiole along the other side of the leaf. Two to 
three days are spent on the first leaf where two molts are completed. 
Larvae then move down the pedicel to the stem where they have the 
option to move toward younger leaves at the tip or toward older 
leaves further down the plant. Nine of ten larval groups observed at 
this juncture moved toward the vine apex (2-sided, Binomial proba- 
bility = 0.04). Later, after apical leaves are eaten, the family de- 
scends along the stem to feed on older leaves. 
Acromis sparsa mothers normally stay behind their moving lar- 
vae and do not appear to influence their movements. When larvae 
stop feeding they form a tight knot of bodies encircling the stem or 
a flat rosette of bodies under a leaf (Fig. lb). Mothers often stand on 
the backs of their larvae but move to the edge or off of the group to 
challenge any approaching arthropod. Larvae spend most of their 
time on the undersurfaces of leaves and at night remain tightly 
aggregated and defended by their mothers. In contrast, Ohaus 
(1909) noted that female Omaspides shielded their aggregated larvae 
during the day, possibly from the effects of the sun, and that larvae 
wandered apart at night to feed. 
Predation on larvae 
Guarding has the appearance of being highly effective at thwart- 
ing predators. However, there are at least two circumstances in 
