1972] 
Henry — Ululodes and Ascaloptynx 
7 
on totally exposed, south-facing embankments of dry arroyos and 
canyons (figure i-a). The insects always seem to choose inclined 
rather than vertical twigs, and seek out the downhill sides of the 
bushes in preference to any other spots; this latter choice gives 
the hatched larvae an unobstructed fall of 50 to 85 cm (18-30 
inches) to the crumbling rocky substrate below. 
U. mexicana eggs are laid on the undersides and towards the tips 
of their twigs, in two long interdigitating rows together totalling 
30 to as many as 52 eggs (figure 2). Each freshly laid egg is light 
grey or cream-grey in color and oblong in shape, averaging 1.6 to 
2.0 mm in length and 0.8 to 1.0 mm in diameter; all the eggs in 
a given egg-mass will be of roughly equivalent size, but different 
egg-masses will vary considerably in their egg dimensions. The eggs 
are laid on end, inclined slightly toward the tip of the twig. They 
are attached to the substrate by a shiny reddish-brown glue. Each 
egg possesses two identical, pale micropyles, about 0.1 mm in diameter, 
axially located one at each end; high power examination reveals 
the micropyle to be saucer-shaped, constructed of approximately 
twenty ribs or channels radiating from a central depression (figure 
3 -A). Except for the micropylar sculpturing and a very slight 
graininess to the balance of the egg surface, the Ululodes chorion 
displays no elaborate fine-stucture. 
Figure 3. Micropyles of Ululodes mexicana (A) and Ascaloptynx 
furciger (B) eggs. 
