250 BOARD OF AGRICULTURE. 



as late as the 23d of September. As already stated, there is 

 great irregularity in the development of individuals from the 

 same parent; and there is little doubt in my mind, that, 

 while the production of a third generation is the exception, 

 it may in some years prove the rule. 



Regarding the manner of hibernation, — whether as eggs, 

 larva, chrysalis, or moth, — there has been great diversity of 

 opinion among observers. 



Assuming that eggs may be laid in early fall as well as in 

 spring, the following questions must be considered : 1st, 

 whether the eggs laid in autumn hibernate as such, or 

 whether the larvae first hatch, and hibernate while small; 

 2d, whether those laid in spring are from moths which 

 issued at that season, after hibernating as chrysalides, or by 

 such as issued the preceding fall, and hibernated as moths. 



As bearing on the first question, it is interesting to note 

 that the European species of the genus, so far as their habits 

 are known, hibernate in the larva state. Quite a large pro- 

 portion of our closely-allied cut-worms are also known to 

 thus hibernate. It would seem, therefore, that, in default of 

 direct observation, we have no good reason for assuming that 

 the eggs laid in autumn necessarily hibernate as such ; and 

 the delicacy of the shell, and rapidity with which they hatch 

 under moderate heat, renders their hibernation extremely 

 improbable. But, while these analogies would indicate that 

 the insect may possibly winter in the larva state, all the 

 other facts point to the conclusion that the proportion 

 that so winters, if any do, is very small. Instead of abound- 

 ing in a wet spring, when their favorite haunts are over- 

 flowed, they would be well-nigh drowned out, on the hypothe- 

 sis that they had been wintering there as larvae. 



As bearing on the second question, we have certain facts 

 which indicate that some of the pupa hibernate, the propor- 

 tion undoubtedly increasing as we go north. 

 But the weight of evidence goes to show that 

 The Pupa, the insect passes the winter principally in 

 the perfect state, in which state alone it has actually been 

 found in winter. From the foregoing considerations I think 

 we may safely conclude, that — taking our whole country, 

 with its varied climate — there is no state in which the 

 army-worm can be said to solely pass the winter; that, ac- 



