He would sometimes work an hour in these ways before the fly would get into a favorable position.

I fed him every day or tw r o until May 15th, when he spun a spherical cocoon around him, and remained enclosed until June 25th, a very hot day, when he came partly out, and leaving his pupa skin half in the cocoon appeared as a perfect fly, but did not spread his wings completely.

While the ant-lions pit found by Mr Emerton was a solitai-y one, no others being found, Mr Birge records his discovery of a large colony of ant-lions in a sheltered, sandy place, under a cliff, in Albany County, New York.

In August, 1871, the colony numbered rather more than six hundred individuals, but on July 6, 1872, there were scarcely half that number.

Another colony, at a different locality, but in the same county, observed in 1871, consisted of some three hundred members.