COCOON, PUPA, AND MOTH 23 



the evening, and lyromethea at two in the afternoon. 

 Promethea has been more regular, and the males begin 

 to fly by three o'clock in the afternoon, and are so com- 

 mon that one female often attracts thirty or forty males. 

 , The sphingid moths are less to be depended upon, 

 emerging at almost any time between dawn and mid- 

 night. These moths have tongues, some very long 

 ones, and fly for food, some at dusk, some later, and a 

 few species in broad daylight. They have little or no 

 odor perceptible to us, and we think that this is be- 

 cause both sexes fly to the same kinds of flowers for 

 the nectar upon which they feed, and the males meet 

 the females in this way without needing any odor to 

 guide them. This is a theory of ours which we have 

 not seen advanced by others, and we give it as a 

 theory although convinced that it is a fact. 



As the whole duty of the caterpillar is to eat and 

 live to grow up, so the whole duty of the moth is to 

 reproduce its kind. To do this male and female must 

 mate, and the female must lay her eggs. Moths which 

 fly in the daytime usually mate in the sunshine, and 

 the dusk-flying and night-flying moths mate after sun- 

 set. In most cases they remain mated for several 

 hours, rest quiet awhile, and then the female begins to 

 oviposit, or lay her eggs. Egg-laying is not a short 

 process. The eggs are growing in the body of the 

 moth, 'and as they ripen they must be disposed of 

 whether they are fertile or not. Near the end of the 

 abdomen is the little pouch which receives the sperma- 

 tozoa in mating, and, as an Qgg passes the opening of 

 this pouch on its way to the ovipositor, the pressure 

 forces one or more spermatozoa out of the pouch, one 



