EEVISION OF NEARCTIC TERMITES. 151 



SWARMING, 



The colonizing individuals of Reticulitermes favipes usually swarm 

 in the morning during April and early May in the vicinity of Washing- 

 ton, District of Columbia. 



On April 18, 1912, nymphs of the first form (with long wing pads) 

 of R. fiavipes were fully developed and ready for the final molt in 

 colonies at Falls Church, Fairfax County, Virginia. The quiescent 

 stage was passed through and the final molt occmTed from April 18 

 to 27. The first swarm in large numbers was on May 8. On May 14 

 swarms occurred in lesser numbers. In 1913 the nymphs were 

 mature on April 8, the final molt taking place from April 8 to 17; 

 the swarm occurred on April 25, 1913. In 1914 these nymphs were 

 mature on April 22, the final molt occurred from April 22 to May 2, 

 and the insects swarmed on May 10. In 1915 nymphs of the first 

 form were mature on April 18, the final molt took place from April 

 18 to 27, and the swarm occurred on April 27 and May 6. 



Apparently nymphs of the first and second reproductive forms may 

 attain their full mature length in the autumn. During late October 

 and November, 1918, nymphs were found in colonies at Falls Church, 

 Virginia, on which the wing pads were of full length and with a light- 

 pinkish pigmentation to the eyes, as Dobson has found to be the case 

 in the vicinity of Boston, Massachusetts. However, full maturity 

 of the nymphs of the first form, with the attainment of opaqueness of 

 the wing pads and fuller pigment to the eyes, is not attained until 

 spring (the last of March or first of April) in Virginia. 



On May 6, 1915, sexual adults emerged at 8.30 a. m. from railway 

 ties and the wooden platform of the electric railway station at Falls 

 Church, Virginia. Again on May 6, 1915, S. A. Rohwer observed a 

 small swarm emerge from the front porch of a cottage near East 

 Falls Church, Virginia. The emergence began at 8.15 a. m. and lasted 

 until 8.35 a. m. ; it was at its maximum at 8.25. Ail of the insects 

 flew away to the southeast. In 1916 nymphs were mature on April 

 24, the insects passed through the final molt from April 26 to May 2, 

 and the swarm occurred on May 8. On May 8, 1916, a swarm 

 occurred from the electric railway station at Falls Church, Virginia, 

 at 8.20 a. m. Farther north the swarm occurs later, usually the last 

 of May or in early June, 



During the latter part of April, 1912, nymphs with short wing 

 pads, or those of the second form (Lespes), were found m colonies 

 at Falls Church, Virginia. These nymphs appear to be more active 

 than nymphs of the first form; they have but slight pigmentation of 

 the compound eye. Nymphs of the first form have a reddish-brown 

 pigmentation to the compound eyes. 



