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Psyche 
[Vol. 94 
these has gregarious larvae. A. sparsa is probably the most impor- 
tant herbivore on M. umbellata because of its abundance through- 
out the wet season and its exploitation of apical foliage. 
Seasonality 
Acromis sparsa populations were not systematically censused so I 
can only present a subjective account of activity through the year. 
Reproduction ceases during the dry season, January through April 
of most years. The few adults observed during this period were 
usually associated with host plants rooted in permanently moist 
habitats. The onset of the rains in early or mid May brings increased 
growth by the host plant and the reappearance of A. sparsa males 
and females on new growth. Females immediately begin to oviposit. 
A second round of mating and oviposition begins in late June and 
early July. Several more synchronized reproductive bouts follow at 
approximately two month intervals before dry season conditions set 
in. Although abundance appeared greatest in the mid wet season 
there were few times when adults could not be found in quantity just 
by inspecting the host plant. There were exceptions such as when 
females were guarding pupae or periods following the emergence 
and first feeding of tenerals. Adults and the larval groups they were 
attending also suddenly became rare during extended rainless peri- 
ods within the wet seasons of some years. 
The Egg Stage. 
Location and composition of the egg mass 
Eggs were deposited in masses (Fig. la) attached to the undersur- 
faces of leaves. Each egg is anchored to the midrib by a flexible, 
lacquer-like thread which fuses with other threads producing a short 
(3-5 mm) pedicel holding the egg mass out toward the leaf apex. 
Eggs are smooth and ovate (0.5 X 1.5 mm), and are stuck firmly to 
one another during oviposition in two to three orderly layers form- 
ing the final 10-15 mm of the egg mass. The stiffened egg mass 
provides a roosting platform for the guarding mother during egg 
development. 
Although oviposition is often under the first or second unfolded 
leaf, egg masses are often encountered under the third, fourth or 
fifth leaf since several new leaves normally unfold during the 12 days 
it takes eggs to develop (Table 1). The distal portion of many leaves 
