238 Forty- FOURTH Report on the State Museum 



and hosts are killed in this manner.* By this means and by unob- 

 served flight, their number continues to decrease toward the latter 

 part of the month, and by the first of May, the last of the invaders 

 has disappeared. 



Interesting Features in Chloropisca. 



In the above recital, several points of interest in the history and 

 economy of the fly may be noticed, the chief of which are these: 

 Leaving its food-plant each season in the month of August (heat of 

 summer), and speedily taking possession of quarters where it is to 

 pass the autumn and winter in inactivity and hibernation; its occu- 

 pancy each year of the same room in a house on its north or northerly 

 side; its awakening into activity in early spring and appearance in 

 myriads; its gathering on the outer wall of the house and disappear- 

 ance therefrom during the month of April; its flight to its unknown 

 food-plant; and lastly, its occurrence in so few localities. How 

 mysterious the instinct, or the principle of heredity that can guide 

 each year the new brood upon their emerging from the plants within 

 which they were developed, to the particular house and to the 

 identical room which their parents had occupied for their hibernation. 

 This, without parental guidance or direction, for as throughout the 

 insect world, with few exceptions, the parents die before their offspring 

 come into existence,f so in this instance, the Chloropisca dies soon 

 after it has done all that it can do for its progeny in depositing its 

 eggs upon the plants which will nourish and carry them to maturity. 



Where Does Chloropisca Breed? 



In the hope that some clue to the source of the Chloropisca visita- 

 tions and to its selection of hibernating quarters might be obtained, 

 request was made of Mrs. Grraves for some account of her house, and 

 its immediate surroundings. From her satisfactory reply, we extract 

 the following : 



The house is brick, three stories and an attic. It faces nearly east, 

 is on a corner lot, 140 feet from the street in front, and 120 feet from 

 the street on the north side. The lot, all of which is in lawn, except a 

 plot of about a hundred square feet reserved for flowers, is 200 feet 

 on the east side and 280 feet deep on the north side: then comes the 

 flower garden, and back of that again more grass, old orchard, and 

 small fruits, ending at the foot of a steep hill covered on the north 

 side from street to top with a dense growth of pine trees, with a few 



* Mrs. Graves had swept up and burned over a half pint of the flies in the second week 

 of April. 



tExceptions are found in the ants, bees, and termites, and according to Eirby and 

 Spence, in certain species among the SpliecidcB, Tenthredinidce, Scolytidce, Fentatomidoe, and 

 Forficulidas. 



