Hugh Scott 109 



of fly-food, etc., they also flew, ran and fed in bright light and exposed 

 places. They appeared to eat a variety of things including dead maggots, 

 puparia, and dead flies; possibly also the fly-food, and mouldy cheese 

 (which they frequented in large numbers) ; while they repeatedly visited 

 a shallow dish of very weak sugar-solution. The evidence was against 

 their killing fly-maggots, as the following records of observations show: 



29. V. 1917. A beetle was twice seen to seize a living half-grown 

 Musca-mSiggot, both times dropping it and finally leaving it alive; the 

 beetle then seized a second maggot, held it a few moments, then dropped 

 it and left it also alive. 



19. iv. 1917. A number of adult Necrobia were seen eating dead, 

 small, partly grown, blowfly-larvae. In one place four beetles were busy 

 on a single maggot, and during part of the time that they were watched 

 as many as six were there; in a second case another three or four beetles 

 were also busy on a single dead maggot. The working of the beetles' jaws 

 was watched, and they did not appear to tear the maggots, but somehow 

 to extract all the soft parts and leave the flabby, empty, skins to all 

 appearance intact. The eagerness with which the beetles crowded to 

 these two dead maggots, though there were in the same vessel large 

 numbers of living ones of all sizes, leads one to suppose that they do 

 not readily kill maggots; from what cause the two dead maggots had 

 died is not known. 



4. V. 1917. Three or Jour beetles seen greedily eating the soft parts 

 of a blowfly-pupa, the puparium of which was broken open in some 

 way (not, I think, by the beetles). 



On another occasion three Necrobia emerged from the pupal stage in a 

 small vessel. A sound puparium of Phormia coerulea had been opened 

 along the same sutures as those used by an emerging fly, and the dried, 

 mummified remains of the fly-nymph were found lying at a little distance 

 from the empty puparium. This case is enigmatic: the puparium had 

 not been opened before the beetles pupated, and the fly-nymph did not 

 look developed enough to have emerged of its own accord. Could the 

 beetles have broken open the puparium along the normal lines of weak- 

 ness, and dragged out the nymph? 



1. V. 1917. An adult Necrobia watched eating the soft parts of the 

 abdomen of a dead blowfly, which was lying on its back; two others 

 near it had also had their abdomens eaten out. 



29. V. 1917. Two of the beetles seen eating one dead, newly- 

 emerged housefly : no proof as to whether they had killed it or not. 



