1006] 
KXAB—SWAItMIXG OF CVLEX PIPIEXS 
120 
near London, is given In’ Douglas. During ten days he observed “the air tliiek with 
millions of them, at times charging in close column uj) the road, like a squadron of 
cavalry, at other times engaged in dancing uj) and down, after the manner of their 
race.” These swarms were in evidence only during the hour before dark and it 
apjicars were over or near the road, within reach of the riding whips and sticks of the 
“ pmfannin rulgihs'.” Near by “are several tall trees, and round the top of the high- 
est one only, at the same hour of the evening that the periodical saltatory performances 
are going on in the road, enormous swarms of gnats congregate. At first they a])pear 
as a small black cloud curling about the ends of the branches, and soon, when the air 
is calm, rising in a close column, like smoke from a chimney, for a distance of some 
20 or 30 feet, the bulk gradually becoming more grey and attenuated until lost to 
sight in the u])ward progress. IMien a breeze is moving, the insects, always pre- 
serving clo.se order, are blown out laterally, and after skirmishing with the wind 
return to their cover among the top leaves of the tree.” This last remark may be an 
assumption and at such distance from the ground could hardly have been baseil upon 
actual observation. Douglas suspects that the species in the tree w’as “not the same 
as that of the acrobats of the road,” and with right; unfortunately neither form was 
definitely identified. It further appears from the remarks of Douglas that the.se 
swarms are an annual occurrence, only that the number of individuals varies 
greatly from year to year. 
In all the foregoing notes the writers failed to notice the true function of these 
gatherings of Xemocera. However it had not escaped that keen observer Gilbert 
White. He was evidently uncertain of the identity of the insects concerned, for in his 
posthumou.sly published notes he calls them “empcdes or tipulae.” Speaking of 
their swarms at evening he says: “At this juncture they sjwrt and copulate; as it 
grows more ilark they retire. All ilay they hide in the hedges. As they ri.se in a 
cloud they ajijiear like smoke.” No further mention of co])ulation in connection 
with swarming a|)pears until Taschenberg’s popular account of Culex pipieri.s, ]iub- 
lished in 1882. He notes their habit of gathering at the gables of houses and other 
prominences and describes how the females fly to the swarm of males to effect copu- 
lation. In the notes on the swarming of Chironomidae which follow, Taschenberg 
describes the formation over trees ami in tall columns, and we are left to infer that 
the Culex swarms do not assume the columnar form — at least not in the same degree. 
Theobald’s brief, disjointed notes on the ])airing and swarming of mosrpiitoes 
would hardly convey the correct impression to the lay mind. He corroborates Tasch- 
enberg’s statement that in Culex pipien.s- the females fly to the males to copulate but 
he failed to note that the males congregate about prominent objects. The brief 
