ON THE LIFE HTSTOET OF UGIMYA. « 



The bottom of this is membranous and leaves only a narrow slit through 

 which air is allowed to pass in. Again, the bottom as well as the whole 

 inside walls of the cup is thickly covered with minute hairs. 



Habitat. — The adult flies generally begin to appear in the middle 

 of April. They are very active, and their power of flight is so strong 

 that a peculiar sharp sound is heard when they are on wing. When 

 confined in large cages of fine wire gauze they strike their heads so 

 energetically against the cage walls that they die in two or three weeks. 

 Of those which I tried to rear from the pupa stage not one attained 

 sexual maturity. The flies which are hatched out-of-doors are still 

 more active and stronger in their flight. From the time of their first 

 appearance to the beginning of June, they frequent mulberry bushes 

 preferring those which are planted in shady or moist ground or those 

 which are old and languid and bear leaves clustered on their shortened 

 stems or branches. It is a very strange fact that those which thus 

 frequent the bushes are always females, and I have never obtained even 

 a single specimen of the male. Besides mulberry bushes, female flies 

 may sometimes be found on grassy grounds which are overshadowed 

 by thickly branched trees; but here also I have not found a single male 

 fly. Where the male fly does find its home remains unknown to me 

 up to the present time. 



Usually the time when the female flies appear is contemporaneous 

 with the breeding season of the silkworm. Although the flies then 

 occur in large numbers, they would not ordinarily be seen by a person 

 visiting localities frequented by them, unless he has a clear idea of 

 their form and habits. They have a very acute sense of hearing, and a 

 very slight motion or sound in the bushes in which they are resting, 

 causes them to fly away instantly. If, however, persons well acquainted 

 with their fi)rm and habits wait in silence or walk as quietly as possible 

 in the bushes, they will then perceive the female flies resting on the 



