114 A NOVEL LIFEBOAT. 



plants, for the larva is easily discovered holding 

 on to them a little below the surface of the water. 

 He is a long, round, ugly-looking grub, divided 

 into twelve segments or rings. The second pair 

 of feet are prehensile, and used for holding on by. 

 He is rather active when undisturbed, but the 

 slightest touch and he hangs by the feet, exactly 

 resembling then a bit of dead rush. When the 

 larva has attained its full growth, it spins a small 

 delicately-fine silken bag, in which it changes to 

 the pupa state ; this bag is invariably left open at 

 the top, and, being spun the long way of the 

 stalk to which it is affixed, the pupa is in an up- 

 right position, and the head of the pupa protrudes 

 a little way out of the bag. Four hair-like fila- 

 ments, like horns, project from the head of the 

 pupa, and are supposed to be breathing organs. 

 About the end of June the delicate little fly bursts 

 from its sarcophagus, and prepares for an aerial 

 existence; and a contrivance utterly different 

 from the mosquito boat, yet equally beautiful 

 and effective, aids the newly-liberated captive to 

 escape being drowned. Maturity attained, the 

 pupa-case splits down the back, and the end of 

 the silken bag being open, out creeps the fly, 

 not into the water, but into a minute silken 

 balloon, a part of the pupa-case, or, I imagine, the 



