THE AMERICAN BOTANIST 83 



surface of the leaf, he poured sand upon it, distributing the 

 weight equally, and it was not until 400 pounds, equivalent to 

 the weight of three grown men had been deposited upon it, 

 that the kaf sank. 



"A most remarkable peculiarity about the under surface 

 of the leaf is the way in which it is covered with long, sharp 

 spines — some of them more than an inch in length. As the 

 upper surface is without them it goes to show that whatever 

 it is that it needs protection against, is something which at- 

 tacks under water. It is scarcely likely to be fish for fish of 

 the size to do damage would hardly live upon green stuff. 

 But in its own river, the Amazon, we find an animal of the 

 order Sirenia known as the Manati {Manatus inunguis) and 

 this species, peculiar to the Amazon and its lagoons and tribu- 

 taries, feeds exclusively upon aquatic plants from underneath 

 the water. It is a seal-like animal 7 to 8 feet long with paddles 

 for fore limbs and was once very common. It has a peculiar 

 method of feeding; the long upper lip is slit vertically into two 

 finger-like halves and these act as nippers, pinching off and 

 pushing into the mouth the water plants on which it lives. 

 The skin of the body is thick but that of the lips is thin and 

 there can be little, doubt but that the plant evolved the spines 

 to protect itself against the Manati or similar enemies with 

 tender mouths." 



To the foregoing account we add some notes on this 

 species from The American Botanist for May 1917. Since 

 the volume from which they are taken is now out of print 

 they may prove worth reprinting. 



Probably the most gigantic leaves in the world are those 

 of the great water lily, Victoria rcgia, which grows in the 

 quiet waters of northern Brazil and Guiana. Paul Marcoy an 

 early traveller claims to have measured some that were more 



