No doubt these dragons of the air are to be counted as among our greatest friends, and in places in the East where life is made a burden by that humming, stinging pest, the mosquito, its presence in great numbers helps amazingly in keeping down the day-flying forms of that insect. It has gone into the Hawaiian Islands with the mosquito and has learned there to breed in the water found on the leaves of lilies growing on dry land. Perhaps someone will find a way to domesticate this creature and make it live upon the house flies around the house. As a first step, Needham has fed the larvæ on bits of meat. Sharpe, the British authority, has observed a dragon-fly returning again and again to the same bush, and Westwood believes he saw the same individual hawking for several weeks together over the same small pond. [Illustration] DRAGON-FLY NYMPH MASKED (_Libellulid_) As Kellogg says, it must, indeed, be worth more than a week of study in the house to see just once the transformation of one of these mud dragons from the bottom of a pond into a beautiful dragon of the air,--a dragon-fly. Of all the strange, weird monsters with which I have ever had to deal, this water one seems somehow weirdest. It reminds me of those sandy-colored, deep-sea fishes which, snuggling under the sand of the sea bottom, wait for their prey to come along and then dart out and seize them with their powerful jaws. The mud dragon has a mask which, for the purpose, is certainly the most effective thing one can imagine. Its victims must be greatly surprised to see the mask drop, revealing a sheep-like nose, mouth, and lips, while the mask itself opening out and splitting down the middle, becomes a pair of needle-margined, powerful claws so strong that even fishes are sometimes caught and held by them. It is strange to think of this dragon concealing its claws by making a shield of them to cover its ugly face while it waits in ambush for its game. Its eyes and body are the color of mud and must be very hard to see. This photograph shows the mask in place, the grinning mouth a long curved slit across the face, while resting on the ground, as one would rest one's elbow on the table, is the powerful claw arm, so strong that you would find it difficult to pull the mask away, or having done so to keep it down. [Illustration] DRAGON-FLY NYMPH UNMASKED (_Libellulid_) Pulled down from the mud dragon's sheep-nosed face, the mask is resting on the ground. It can be stretched out much further and also opened up to form a pair of powerful claws. Along the edge of the mask is a fringe of inward-pointing spines like those which edge the leaf margins of a venus flytrap. The eyes are large and many-faceted and form the blunt-pointed corners of its head.