the last twenty years, many of them

being today obtainable at the cost of a few dollars per specimen. The same thing is true of the brilliant Ornithopteras of the Indo-Malay region, those huge butterflies with a wing expanse of from five to eight inches, and whose color is a combination of velvety black with either green, yellow, orange or blue. Fifty years ago in order to secure these species it was necessary for a collector practically to take his life in his hands and penetrate unknown regions inhabited by fierce head-hunting tribes; today, owing to the advance of civilization and the improvement in means of transportation, numbers of the species appear on the market each year; the natives have been trained to hunt for the caterpillars and breed perfect specimens of the insect, and whereas in former years collectors would regard even tattered and torn specimens as almost priceless, today for a few dollars a specimen perfect in every respect may be purchased.

In the Palaearctic region all species of butterflies from Tibet have always commanded a high price owing to the

Many butterflies are easily raised in captivity from cocoons picked off trees