45 
the development of Hristalis tenar from the ecg to the imago. 
I did not find, in entomological literature, any statement about 
the number of days required for the whole development, but I 
found several statements about the pupa-state. Réaumur (LV, 
471) says it is ,eight to ten days, when the weather is fa- 
vorable.“ Swammerdam (p. 257 Germ. ed.) says 16—17 days; 
Taschenberg (in Brehm’s Thierleben, IX, p. 467) — from 12 to 
14 days; Letzner (Schles. Ber. 1856, p. 117) — 13 days. De- 
ducting the eight or ten days of Réaumur (as better adapted 
to a warmer climate than the other statements) from the thirty- 
two of Florentinus, twenty-two or twenty-four days remain, 
which is time enough for the development of eg@ and larva. 
I sum up my analysis of the Bugonia-process of the ancients 
and, in general, the history of this superstition, as follows: 
For centuries the ancients have made efforts to obtain oxen- 
born bees by artificial processes; Florentinus (comp. p. 6) calls 
it ,making bees* (apes facere), which may have been a current 
expression; the essential feature of all these processes con- 
sisted in the zso/ation of the whole carcase, or of a portion of 
it, from the open air. The result obtained were legless larvae, 
which, after a time, changed into bee-like insects; but as 
larvae of bees cannot live in rotten matter, the insects into 
which they changed could not possibly have been honey-bees; 
they were bee-like flies, drone-flies, Hristalis tenax, the only 
flies which have the required qualifications for playing the part 
of oxen-born bees (comp. p. 9). The ancients always mistook 
them for real bees, and never became aware that they did not get 
any honey from them. The assistants of the experiment let the 
flies loose, feeling satisfied with having increased the number 
of ,flower-sucking bees, mothers of honey,“ who ,like their 
forefathers roamed over pastures, bent upon work and hopeful 
of the future* (Ovid. Metam. XV, vy. 366—68; comp, p. 6 for the 
whole passage). 
That this illusion lasted so long, and that the ancients 
never came to distinguish /vista/is from a honey-bee, was prin- 
cipally due to that form of mental inertia, which, at the very 
