264 M LOWER FLORIDA WILDS 



these trees he will find many curious, slender stubs 

 or quill-like growths sometimes a foot in height, 

 projecting above it and attached to the under- 

 ground roots of the tree. These not only provide 

 the tree with oxygen but they bind the mud to- 

 gether and hold all the finer trash which passes 

 through the wider meshes of the mangrove roots. 



Yet another tree is often associated with these 

 called the "black mangrove" though neither it 

 nor the white is really related to the true man- 

 grove. It is Avicennia nitida, a tree which carries 

 on the business of growing these strange pneumato- 

 phores (as the quill-like growths are called) to a 

 greater extent even than does the white mangrove. 

 Here it often becomes a large tree and the mud 

 beneath it, and for some distance away, is usually 

 thickly covered with its quills considerably taller 

 than those of the Laguncularia. It has the habit 

 of viviparity, like the mangrove, but developed 

 differently. Its large flattened seeds germinate 

 on the tree, the two seed lobes or cotyledons being 

 folded, and the roots do not greatly develop until 

 after they have fallen. 



There is a variety of vegetation along the man- 

 grove shore and a little distance back in the 



