V 
3. It illustrates, in the ,Bugonia-craze‘, an interesting 
episode in the history of science, and of the human mind in 
general, which proves how, to use an expression of Réaumur, 
yin the advancement of truth, anything may become an obstacle.‘ 
In order to exhaust the story of the Bugonia, it would be 
necessary to collect al/ the passages, concerning it, which exist 
in ancient and modern literature. To undertake such a task, 
perhaps easy for a philologist, would for me be presumptuous. 
I have made use of such references in so far only as they were 
necessary for the illustration of my principal thesis: , Without 
Eristalis, no Bugonia‘. 
My interest in Hristalis tenax was aroused by the fact that, 
as a Student of Dipterology, I happened to be the first to call 
attention to its sudden appearance in the United States, when, 
on November 5th 1875, I found a specimen on a window in 
Cambridge, Mass. Since then I have been watching its rapid 
progress in North America, and afterwards, its extraordinary 
invasion into New Zealand; in the mean time, quite naturally, 
I was drawn into an inquiry about its previous history. 
The Supplement contains eleven chapters on the following 
subjects : 
I. (p. 39). Analysis of the process of the ancients for 
breeding oxen-born bees. 
Il. (p. 47). The Bugonia from a psychological point of view. 
II. (p. 49). On the gradual revival of Natural Science in 
the XVIIth and XVIIIth centuries; a chapter translated from 
Réaumur, Mém. etc. Vol. I, p. 28—31. 
IV. (p. 52). The inconsistence of Redi in regard to the 
principle: omne vivum ex ovo. 
V. (p. 53). Why the ancient writers, in so many passages 
concerning the Bugonia, derive the origin of hornets from car- 
cases of horses, and often confuse them with wasps. 
VI. (p. 55). The text of the fable of Lessing on the horse- 
born wasp, and that of the passage of Melanchthon about the 
Bugonia. 
