310 Prof. 0. Heer on the House Ant of Madeira. 



ginosa, F., were also seen in the Lake of Zurich ; but it is related 

 that at Schondorf in Wurtemberg, on the same evening, swarms 

 like clouds (to judge from the description), of Mijrmica rubra 

 were moving between three and four o^clock through the coun- 

 try ; and a hke report referring to the same day was made from 

 Soleure, Friburg, Bubendorf and Gelterkinden in the Canton of 

 Basle : whence it is to be inferred that the swarms were moving 

 in a southerly direction. The last great swarms (of Myrmica 

 rubra, F.) we observed on the 11th of August, on the summit 

 of the Uetliberg. Similar phsenomena occur however every year, 

 though not in these environs*. It depends in gi'cat measure on 

 the weather. Should this happen to be fine at the time when 

 the winged ants are quitting the chrysalis state, they all leave 

 their nests at the same moment, and thus form those immense 

 great cloud-like swarms ; on the other hand, should the weather 

 be unfavourable at this epoch, the swarms are distributed over a 

 longer period, and are not therefore so striking. This is indeed 

 the case too with our May Chafers. Let fine ]\Iay weather 

 all at once set in after a wet April, and all at once (in years 

 when they abound) great quantities of them make their ap- 

 pearance, and again after a short time disappear ; but if May 



* The following account, which appeared in most of the leading; journals 

 at the time, is copied from the ' English Churchman ' of Sept. 2, 18.52 

 (No. 505, vol. X. p. 5/5).— Tr. 



"Extraordinary Phcenomenon. — A lover of natural history, who was in 

 Romney Marsh on Tuesday the l/th ult., about 5 p.m., gives the following : 

 — ' 1 saw what appeared to he a column of smoke approaching me, about a 

 quarter of a mile off. On the column reaching me, I found it was composed 

 of red ant-flies. I think the column was a good quarter of a mile in length, 

 and about from 50 to 100 yards in circumference : it quite darkened the 

 sky. After it passed me it went over the river Kother, into which millions 

 and millions of flies fell; and when I crossed it, the water was quite 

 black. I watched the column for a mile and a half, and, notwithstanding 

 the numbers left in the river, and on the trees, hedges, &c. over which it 

 passed, the column appeared undiminished, and like a wreath of dark 

 smoke. The extraordinary thing is, that the ant-flies throughout the whole 

 marsh,thirtymiles in length (aslhearitwas so all through the marsh), should 

 all have taken wing at the same time, and collected together in such vast 

 numbers. A man who was collecting ant-eggs for me, informs me that 

 he found himself covered with them, running up to the tops of the strands 

 of grass and then taking wing. After the flight he scarcely foimd one ant- 

 fly in the nests. Other persons who saw the flight, and who I do not 

 believe intended to exaggerate, considered the length of the column to be 

 a mile. The wind was in the cast, the temperature very sultry, and there 

 was every appearance of a thunder-storm. Had not my man observed the 

 ant-flies rise from the ground, I should have thought that they came from 

 the Continent. The column travelled at the rate of five or six miles an 

 hour. Those persons fond of natural history will find an interesting 

 account of these flights, and the reason, in the 2nd volume of Kirby and 

 Spence, pp. 51, 52.' — Sussex Express." 



