VOL. XIV.] PHILOSOPHICAL TRANSACTIONS. 4^ 



very strange economy of nature yet unsolved; the furthermost bee, says Mr. 

 Willughby, makes her way out along the channel through all the intermediate 

 cartridges, and according as these channels run upwards or downwards in the 

 body of the tree, the maggot bee at the farther or upper end of each channel is 

 first laid, and it should seem both hatched and perfected first, and must either 

 wait imtil the rest be so too, or of necessity, by working through their cases, 

 destroy them. If it be so, it is very strange. But I take it otherwise, and 

 perhaps it will be found by diligent observers hereafter, that that bee which is 

 nearest day, although it be last laid, is yet the first hatched; and I ground my 

 conjecture upon this, that it is probable the eggs in the mother are all fit for 

 laying, or equally ripe and forward, at the time that the first of them was laid, 

 but are not therefore all laid by the dam until she has provided them with 

 meat and a house, each separately, as is the nature of bees ; and yet in recom- 

 pence, the warmth of her body, or rather the daily increasing heat of the sum- 

 mer season, to which the mother bee is continually exposed, whilst the first laid 

 eggs are sheltered in their deep channels, hastens their vitality so much, that 

 they are hatched worms, and begin to feed before the first laid, and consequently 

 are first perfected into bees. But this is conjecture only, and not observation, 

 and to this purpose let me observe to you, that we are not always without our 

 viviparous flies, although in a much colder region than Italy. The first time I 

 took notice of them was the 2d year of the sickness raging in Cambridge, ] 666. 

 1 have of this sort some by me at present, which I do not find cut or described 

 either in Aldrovandus or MoufFet, though this sort of fly be very frequent with 

 us.* And this was not the only strange phenomenon that I observed among 

 insects, besides other things of nature, particularly that year ; for being in har- 

 vest-time at Bessenburn in Cambridgeshire, at the house of Mr. W. A. he in- 

 vited me along with him into the fields, where, says he, " I will show you a 

 wonder;" which, indeed, was so to me, for lifting up the barley cocks with his 

 cane, there appeared millions of maggots on the corn lands, and in their barns 

 too, the floor would be covered with them that fell from the carts. The mag- 

 gots were about half an inch long, no thicker than a pigeon's feather, of a 



• Some few flies are known to be viviparous, the ova hatching internally before the larvae or mag- 

 gots are excluded. The most remarkable of these flies is the musca camaria, Linn. Syst. Nat, edit. 

 12. It is described and accurately figured both by Reaumur and Degeer, and greatly resembles the 

 large blue flesh-fly or musca vomitoria of Linnaeus, but is of a greyer colour, with red eyes. It de- 

 posits its larvae on meat, &c. like that species, and belongs to the second Linnaean division of the 

 genus, viz. niuscce pilosce antennis plumatis. Degeer describes a smaller species of viviparous fly, so 

 nearly resembling the musca camaria in every thing but size, that the same description as to form and 

 colours might serve for both. 



