TENTH RKPOET OF THE STATE ENTOMOLOGIST 475 



i\y is seized, Bittacus would sooner be torn from its support than relin- 

 quish its hold upon the prey. One was seen ia the field just after she 

 had seized a rather large fly; twice she was torn from the supporting 

 stem and forced to fly a short distance, still holding her prey. After 

 quite a struggle the fly was killed. Bittacus will touch nothing but 

 living insects, so far as known. One female killed four house-flies in 

 a day; on another she killed three. In nature they undoubtedly^ 

 destroy large numbers of insects; flies seemed to be preferred, though 

 some small Capsidte, Coleoptera, and Hymenoptera were killed by con- 

 fined individuals. As they are such voracious feeders and by no 

 means rare, since hundreds were seen flitting in the woods inhabited 

 by them, the genus may be ranked among the beneficial insects. It 

 appears to be rather local and, therefore, of little importance in an 

 economic way. In the woods where they abounded the conditions 

 seemed favorable for the multiplication of mosquitoes, yet they were 

 not abundant; possibly their numbers were reduced by the blood- 

 thirsty Bittacus. 



Habits of European Species. 



The following is Dr. Packard's {loc. cit., p. 162) rendering of 

 Brauer's account of an European species: "The imagines, or 

 adult flies, live in a sort of a chamber covered in by leaves, 

 grasses, nettles, etc., forming an airy abode or vivarium. Here 

 they feed upon such flies as enter their habitation. The flies 

 die after laying their eggs in the soil, and the earth at the 

 bottom of the chamber dries up, but in the following April, 

 when the soil is again wet by the spring rains, the larva? hatch out. 

 And now a remarkable fact has been noticed by Brauer. He has 

 observed that if the marshy or wet ground where the female Bittaci 

 customarily lay their eggs does not dry up, no females appear until the 

 second year following; so that the eggs lie over unhatched two years. 

 The first condition of their hatching is a complete drying of the earth 

 in which the eggs lie; the second condition is a succeeding thorough 

 wetting of the ground in spring. If the ground remains dry from 

 want of snow in the winter or of rain in the spring, and there follows 

 in the next summer a very thorough wetting of the soil, then the time 

 of appearance of the adult will be retarded three or four months." 



In this country no vivarium or chamber has been found as yet. 

 The insects were observed for hours in their native haunts, where 

 they were seen to rise in numbers from low bushes and ferns upon 

 the approach of an intruder, yet they were rarely seen within three 

 inches of the ground. In this connection it would be interesting 



