152 BULLETIN 108, UNITED STATES NATIONAL MUSEUM. 



From March 24, 1919, to April 8, 1919, nymplis of the second form 

 oiflavipes were common in colonies at Falls Church, Virginia. 



By April 21, 1919, at Falls Church, Virginia, it was no longer pos- 

 sible to find any nymphs of the second form in colonies ol jlavipes. 

 Most of the first form nymphs had molted and had transformed to 

 winged pigmented adults — mostly with nearly mature pigmentation. 

 It was stiU possible, however, to find some mature nymphs of the first 

 form with opaque wing pads and nymphs which had recently molted 

 and which were in the "airplane stage;" i. e., with the wings as yet 

 unexpanded and extended out from the body as planes. On this date 

 the flower buds of the flowering dogwood (Cornusjlorida) were swelling. 



On April 23, mature and recently molted first form nymphs were 

 stiU present in colonies with winged adults with pigmentation nearly 

 mature. These adults flew when colonies were cut into. A few first 

 flowers of dogwood were out, the general condition being flower buds 

 swelling. 



On April 28, 1919, at Falls Church, Virginia, the winged adults in 

 most colonies had attained mature pigmentation. In a few colonies 

 mature nymphs of the first form with opaque wing pads and recently 

 molted nymphs in the "airplane stage " were present. The blossoms 

 of dogwood were half out. A few young nymphs of reproductive 

 forms with short wing pads were found in colonies. 



By April 30 the adults had swarmed from colonies. Dogwood was 

 nearly in fuU bloom. 



Nymphs of both first and second forms pass through quiescent 

 stages during the final molt, which are of comparatively short dura- 

 tion. On April 25, 1912, at Falls Church, Virginia, the first molting 

 nymphs of the second form were observed in colonies; April 22, 1913 

 and 1914; April 27, 1916. 



On April 5, 1915, a swarm occurred at Washington, District of 

 Columbia. In Washington swarming sometimes occurs very early 

 in infested buildings. On February 14, 1916, a swarm occurred in 

 the dark, damp heated basement of a building; on February 19, 

 1917, a swarm emerged from damaged flooring in a building in 

 Washington, and on February 16, March 14, 26, 31, and April 2 and 

 13, 1918. Later swarms in infested buildings at Washington, 

 occurred on April 13 and May 6, 1918. 



In the extreme south this insect swarms earlier — Palatka, Florida, 

 February, 1868, and February 13, 1875. However, this species 

 swarmed as late as May 19, 1875, at Enterprise, Florida (Hubbard), 

 and May 11, 1883, at Crescent City, Florida (Hubbard). On March 

 4, 1919, winged pigmented adults, ready to swarm, were found in a 

 colony in a stump at Ortega, near Jacksonville, Florida; first flowers 

 were out on flowering dogwood on this date. Yet a swarm occurred 



