104 THE VICTOBIAN NATURALIST. 



and forethought for her offspring. The object of this small 

 insect in constructing a boat-shaped raft, which easily floats- 

 upon the water's surface, is to prevent her eggs from sinking, 

 which they most certainly would do were they dropped singly 

 into the water. The eggs, which form this raft, themselves are- 

 much in the shape of flasks, rather pointed at the upper end 

 and rounded at the under, brownish in colour, and coated with. 

 a glutinous fluid. 



The first care of the mother mosquito is to fix herself by the- 

 four forelegs to the side of a floating twig or leaf, or the first 

 thing that may come to her reach, with her body level with, and 

 resting on the water, excepting the last segment which is^ 

 slightly curved upwards. She now crosses the two hind legs 

 like a pair of scissors when open, the inner opening slightly 

 bent, thus forming a frame to receive the eggs into. Now she 

 brings this inner opening to the raised portion of her body, and 

 deposits one egg in it ; on each side of this she places another- 

 egg, which adheres by means of the gluey substance they are 

 coated with. Thus the stern of her boat is now made. 



She proceeds in this way to add eggs one by one in a vertical 

 position, and pushes the whole mass gradually from her as the 

 boat increases in size. When half finished she uncrosses the 

 two hind legs, and places them parallel, and so continues until 

 she' wishes to form the bow of the boat, when she draws the 

 hind legs gradually together, placing eggs between them, until 

 the bow is formed like the stern. 



Kirby describes this little raft, which is now finished, as- 

 " resembling a London wherry, being sharp and high (as sailors- 

 would say) fore and aft, convex below and concave above, and 

 always floating on its keel. So well are they constructed that,, 

 do what you may, you cannot possibly make them sink. I have 

 held them under water for several minutes, but they invariably, 

 rose to the surface, again floating on their keel, apparently quite 

 dry. Probably the glutinous fluid they are coated with prevents- 

 the water staying on them." 



Kirby tried several experiments on these boats. He says: — 

 •' The most violent agitation of the water cannot sink them,, 

 and — what is still a desideratum in our life boats — though 

 hollow, they never become filled with water, even though exposed. 

 To further test this, he placed half a dozen of these boats upon- 

 the surface cf a tumbler half full of water, and then poured 

 upon them a stream of that element from the mouth of a quart 

 bottle held a foot above them. Yet, after this treatment, which 

 was so rough as to actually project one out of the glass, he 

 found them floating, as before, upon their keels, and not a drop- 

 of water within the cavity. Such marvellous instinct cannot 

 but impress even the most careless observer with the wonderful. 



