5'> [A\ig\ist, 



reason, takes to be its food. Loew (Verh. Zool. Bot. G-es., 1861, p. 

 395) found the larva in a swallow's nest, and took it for that of 

 Therevn, a statement which Prauenfeld, I. c, corrects, no doubt, with 

 good reason. Damianitch (Verb. Zool. Bot. Ges., 1865, p. 237) found 

 a cocoon of Saturnia fyri, inside of which, among remains of the pupa, 

 he discovered a chrysalis ; he bred Scenopinus niger from it ; he gives 

 a good figure of the chrysalis, which, he says, agrees in the main with 

 the figure previously given by L. Dufour of the chrysalis of Sc.fene- 

 sfralis (the differences are probably specific). Packard (Proc. Essex 

 Institute, 1867, p. 93) gives a rough figure of the larva, which, he says, 

 was found feeding on carpets. V. Heyden bred S. niger from dry, 

 rotten wood (Jaennicke, Berl. Ent. Zeit., 1867, p. 78). Perris (In- 

 sectes du pin maritime, Dipteres ; Ann. Soc. Ent., 1870, p. 226) found 

 larvse and pupfe in a branch of Cratcegus, which contained larvae of 

 Ptiniis germanus, and in pine boards, containing larvae of HyJotrupes 

 hajulus ; he observed a larva of Scenopinus devouring a chrysalis of 

 Hyloirupes ; he also quotes an observation of Dr. Cartereau, who found 

 in a swallow's nest a pupa of Lucilia dispar, containing the imago of 

 a Scenopinus, which had died in the effort of escaping from it ; Perris 

 concludes by saying, that " this larva, like that of Thereva, feeds on 

 animal substances, that is animal dejections or exuviae, and that it is 

 even carnivorous." Mr. C. O. Waterhouse exhibited at the Entomo- 

 logical Society a Sc. fenestralis bred from the root of Aconitum (Proc. 

 Ent. Soc. Lond., December 7th, 1881 ; Ent. Mo. Mag., January, 1882). 



It seems to me that Perris might have stated more boldly that the 

 larvae of Scenopinus, like that of Thereva, is carnivorous. This is the 

 result which I obtain from the comparison of all the previous observa- 

 tions. The larva does not frequent fungi, rotten wood, swallows' nests, 

 &c., for the sake of vegetable matters, or animal remains, but for the 

 sake of the pupa;, and, perhaps, also of the larvae, which it finds there. 

 And I deduce from this that when it occurs in carpets and horse-hair it 

 is not because it feeds on them, but because it hunts there for the 

 larvae or pupae of the moths or other insects that live in them. 



The long, serpentiform, white larva, very hard to the touch, and 

 very tenacious of life, has several times been brought to me, but it did 

 not occur to me at that time to feed it on larvae or chrysalides of 

 moths. It might be worth while to try the experiment, and thus to 

 prove that the demure little fly is, after all, a useful member of our 

 household. 



Heidelberg : July, 1886. 



