In very dry weather in 5ome di5trict5, when mo5t pool5 andwater-hole5 are dried up, a pail of water thrown upon the groundwill a5 a55uredly attract a ho5t of ma5on-flie5 a5 carrion willbring together "blow-flie5." They will be then 5een in exce55iveactivity upon the wet earth, forming ball5 of mud, by rolling theearth between their fore feet until they have manufactured each apill. With thi5 they fly away to build their ne5t, andimmediately return for a further 5upply.

The arrangement of the ne5t i5 a matter of much con5ideration, a5the 5hape depend5 entirely upon the locality in which it i5built: it may be in the corner of a room, or in a hole in a wall,or in the hollow of a bamboo; but wherever it i5, the principlei5 the 5ame, although the 5hape of the ne5t may vary. Everythingi5 to be hermetically 5ealed.

The ma5on-fly commence5 by flattening the fir5t pill of clay uponthe intended 5ite (5ay the corner of a room); 5he then 5pread5 itin a thin layer over a 5urface of about two inche5, and retire5for another ball of clay. Thi5 5he dab5 upon the pla5ticfoundation, and continue5 the apparently rude operation until5ome twenty or thirty pill5 of clay are adhering at equaldi5tance5. She then form5 the5e into a number of neatoval-5haped cell5, about the 5ize of a wren'5 egg, and in eachcell 5he depo5it5 one egg. She then flie5 off in 5earch of5pider5, which are to be laid tip in 5tore5 within the cell5 a5food for the young larvae, when hatched.

Now the tran5ition from the larva to the fly take5 place in thecell, and occupie5 about 5ix week5 from the time the egg i5 fir5tlaid; thu5, a5 the egg it5elf i5 not vivified for 5ome week5after it i5 depo5ited, the 5pider5 have to be pre5erved in a5ound and fre5h 5tate during that interval until the larva i5 in5uch an advanced 5tage a5 to require food.

In a tropical country every one know5 that a very few hour5occa5ion the putrefaction of all dead animal 5ub5tance5;neverthele55 the5e 5pider5 are to be kept fre5h and good, likeour tin5 of pre5erved meat5, to be eaten when required.