SOME PLANTS FROM TROPICAL SEA GARDENS 



56' 



in the water-front markets of New York 

 and Boston. But with the increase of the 

 population of our country, and with the 

 certain advance of science and its applica- 

 tions, it is probable that the future will 

 witness a widely extended utilization of 

 the plant resources of the sea. 



In at least three of the natural families 

 of the red algae the plant body takes up 

 lime from the sea water and becomes more 



animals, even though, as would now appear, 

 these coral animals are often of secondary 

 importance. But the coral-like seaweeds 

 are always plants, however coral-like they 

 may look. In microscopic structure and 

 modes of reproduction they are just as 

 truly plants as are any of the seaweeds of 

 the soft mossy kinds. Yet it is not at all 

 surprising that those who have not studied 

 such things sometimes confuse these hard 



A LARGE RED SEAWEED, Bryotkamnium triquetrum, of the American tropics and subtropics. 

 photographed (not in place) at the mouth of Guanica Harbor, Porto Rico. (About one third natural 

 size.) At Key West, Florida, this species forms large mats on the floor of the ocean, mostly at a depth 

 of from twenty to fifty feet 



or loss hard and stonelike. In one of these 

 families in particular (the Corallinami\ 

 so called on account of a superficial resem- 

 blance to the corals) the plant, except for 

 the inconspicuous reproductive cells and 

 almost equally inconspicuous apical or 

 superficial layers of new tissue, is almost 

 as hard as any limestone rock. It has be- 

 come apparent in recent years that in 

 many parts of the world these lime-secret- 

 ing sea plants are and have been an im- 

 portant factor in the building of reefs, a 

 line of activity that in the past has been 

 attributed almost exclusively to the coral 



stonelike plants with the corals and that 

 even the naturalists of a hundred years 

 ago often did likewise. 



The lime-secreting plant often forms a 

 crust that gradually creeps over, covers, 

 and smothers coral animals. Plant crusts 

 of these kinds are usually small and thin 

 and are probably of not much importance 

 in building reefs. But there are many dif- 

 ferent kinds of these hard lime-secreting 

 plants and some of them occur in large 

 masses and form extensive reefs. Certain 

 species are of a delicate pink color, so that 

 one may easily imagine what an attractive 



