230 BRITISH ANTS. 



Morley observed males and females flying at Foxhall in September, 

 1892 32 , Crawley mentions a marriage flight at Seaton on September 

 15th, 1912, at 2 p.m. 63 , Charbonnier sent me a winged female to 

 name, which was flying at Tockington on September 27th, 1914, and 

 Beck took a male and female in copula at Swanage on October 6th, 

 1914. A marriage flight had evidently taken place at Weybridge on 

 July 29th, 1913, as I saw many deflated females running about 

 on the heath on each side of the railway station ; several had been 

 captured by workers of Formica rufa and F. sanguined and were being 

 dragged as prey to the nests of the latter ants, and a dead winged 

 female was found in a nest of the last-named species. A marriage 

 flight occurred at Sandown, Isle of Wight, on August 27th, 1913, 

 males being observed in the late afternoon in the garden of my 

 house there, and on the pavements near by, and a female was 

 captured, which had already removed some of her wings 66 . 



Wasmann has pointed out that " On account of the conceal- 

 ment of the inner nest one almost never finds the old queens of 

 L. umbratus, mixtus, brunneus, and emarginatus, whereas they are 

 easily to be found with L. niger, alienus, and flavus."^ This is 

 certainly the case in my experience with umbrata, as, however 

 carefully a colony of this ant has been dug up, I have never found 

 the queen. 



Barnes found nine dealated umbrata females when digging up a 

 nest of Formica sanguinea at Wellington College on September 6th, 

 1902 36 , but it is probable they were only sheltering in the earth 

 after the marriage flight. I have on several occasions found many 

 D. umbrata workers when digging up F. sanguinea nests at 

 Woking, but the two species were most probably not really living 

 together 53 . 



It has been demonstrated both by observations in nature and by 

 experiments in captivity that the newly fertilized female of 

 D. umbrata founds her colony in nests of D. nigra. 



In the summer of 1895 Adlerz observed a colony of D. nigra in 

 Sweden, containing a number of what he took to be D. flava 

 workers, which assisted the nigra workers to carry off the brood 28 , 

 but as suggested by Wasmann the yellow workers were most 

 probably umbrata of the first brood 48 , which always consists of 

 small ants. Adlerz 's explanation of this mixed colony was that 

 the nigra workers had pillaged some flava pupae and hatched them, 

 but this is very improbable. 



On August 1st, 1909, Wasmann discovered near Lippspringe, in 

 Westphalia, a populous colony composed of about one thousand 

 D. nigra workers, one hundred D. umbrata workers, and several 

 males and one winged female of D. umbrata**. 



On May 28th, 1914, Crawley found two mound nests near each 

 other (in a field at Woking) belonging to the same colony, which 

 contained workers of D. umbrata and D. nigra in about equal 



