22 CATERPILLARS AND THEIR MOTHS 



pressure of the blood causes the wings to stretch out 

 longer and wider, as well as thinner, until they have 

 reached their normal size and shape, after which the 

 moth waves them gently as if to dry them, and in a 

 few hours they are stiff and ready for flight. 



Meanwhile the moth exercises its legs, rubs its 

 antennae, uncoils and coils its tongue, if it has one, 

 and seems to be preparing every part for use. Later, 

 if it is a female, it thrusts out of the end of its abdo- 

 men the ovipositor, or egg-placer, usually a yellowish, 

 short tube, and is ready for mating. 



In confinement different species of attacine moths 

 can be expected to emerge at regular hours of the day, 

 and ours seldom have varied much from those hours. 

 For instance, the large attacine moths usually have 

 come out between seven o'clock in the morning and 

 noon, cecropia pretty regularly between nine and ten 

 o'clock, and promethea a little earlier. These moths do 

 not feed, and, in our experience, the females do not 

 fly until the need of egg-laying forces them to do so. 

 They have a strong odor — "a regular menagerie 

 smell," it has been called — which enables the males to 

 find them as they hang from the twigs out of doors, or 

 the side of the cage indoors. This odor is diffused all 

 through the day and is carried by the air to great dis- 

 tances, so that by the time the males begin to fly some 

 are pretty sure to be attracted by it, follow it up, fly- 

 ing against the wind, and find the female. We our- 

 selves have often found cecropia by following the odor. 

 The hour of emergence cannot be said to be always 

 the same, however, for one or two cecropias have come 

 out in the afternoon in our boxes, and one emerged in 



