November 11, 1898.] 



SCIENCE. 



659 



the tops of the main dunes and in salt 

 marshes, but play their most important role 

 in dune building. Growing in bunches, as 

 they do, they catch and hold the sand which 

 is continually drifting about at the base of 

 the dune, and in the course of time banks 

 of increasing height are formed about them 

 until a second line of dunes, nearer the 

 water, is formed. 



The islands and keys along the mainland 

 from Biscayne Bay to Key West are of 

 coral formation. Here the vegetation, 

 which is mostly tropical, differs totally 

 from that of the sand dunes above de- 

 scribed; the 'mangrove formation,' so well 

 described by Schimper and Karsten, being 

 the most common. Probably the most in- 

 teresting strand plant of the open beaches 

 in this section is Agave deeipiens, which is 

 widely distributed along the strand of 

 tropical Florida, being disseminated almost 

 wholly by bulblets produced in place of the 

 flowers. These bulblets are not injured by 

 extended soaking in salt water. They are 

 usually carried here and there by the tide, 

 are thrown up on the beach by the waves, 

 take root, and produce new plants. 



The islands along the west coast of 

 Florida are largely of mangrove formation. 

 Shoals are formed by the action of the 

 water, and on these the mangrove finally 

 takes root, and the roots catch and retain 

 sea weeds and other floating matter, thus 

 gradually building up a humus earth 

 around the trees. On the seaward side 

 these trees interrupt the waves, and thus in 

 time a bank of shell is thrown up, and 

 where the forces continue for long periods 

 m.ore or less extended islands are formed. 

 In their simplest form these consist of a 

 low ridge along the seaward shore, composed 

 mainly of fragments of shell thrown up by 

 the waves, and a mangrove swamp on the 

 landward side. In time the interior of the 

 forming island becomes too high for man- 

 grove vegetation, and the latter gradually 



gives place to the typical hammock vegeta- 

 tion, that is, live oak, palmetto, etc., which 

 in Florida usually covers all soils rich in 

 humus. The typical islands along this 

 section of the coast, therefore, are composed 

 of a central tract of hammock bordered on 

 the seaward side by a belt of sterile shell 

 land from 100 to 600 feet wide and on the 

 landward side by a mangrove swamp. 



The most characteristic plants of the 

 mangrove formation are Rhizophora mangle, 

 Avicennia nitida, Laguncidaria racemosa, etc. 

 The most characteristic of the shell belt on 

 the seaward side are probably Forestiera poru- 

 losa, Myrsine rapanea, Coecoloba uvifera, Ju- 

 niperus virginiana, etc. Here, as on the east 

 coast, Iva imbricata, Cakile maritima, Ipomcea 

 pes-cuprce, etc., grow abundantly on the 

 margin of the water. 



Notes on the relative infrequency of Fungi upon 

 the Trans-Missouri Plains and the adjacent 

 foothills of the Rocky Mountains. Peofessor 

 C. E. Bessey. (Read by title.) 



Fungus gardening as pi'aetieed by the Termites 

 in West Africa and Java. David G. 

 Fairchild and O. F. Cook. 

 In the absence of Mr. O. F. Cook the 

 matter relating to Javanese Termites alone 

 was given. Mr. Fairchild called attention 

 to the presence of three species of Termites 

 as yet unidentified which are fungus 

 growers. The nests of these insects are 

 composed of two parts : (1) the earthen- 

 walled galleries, consisting of tunnels in 

 every direction through the earth or even 

 above it, made by cementing together 

 mouthfuls of mud which the workers of 

 these colony-producing insects deposit like 

 brick layers on a wall ; and (2) the wooden 

 mache combs which form the gardens of 

 the Termites, which are built up of wood 

 particles that have passed through the 

 bodies of the workers. These combs are 

 miniature labyrinths, the walls of the pas- 

 sages being covered, top, bottom and sides, 



