590 BOWMAN— ECOLOGY AND 



in view material was carefully collected of all parts of the plants 

 and preserved for future study. Meanwhile, the transpiration work 

 was pursued and some attempt made to correlate the structure of 

 special organs with the physiological functions in these plants which 

 grow in such peculiar conditions. 



In the winter of 191 5-16 the study of these structures was car- 

 ried on at the botanical laboratory of the University of Pennsyl- 

 vania and again in June, 1916, a full season was spent at the Tor- 

 tugas Laboratory on the physiology and also the biochemical relations 

 of certain products in the hypocotyls. Short reports of the two sum- 

 mers' work were published in the year books of the Carnegie In- 

 stitution.^ 



While considerable work has been done on the mangroves of 

 the tropics in general, this has been mostly of a purely morpho- 

 logical nature, or ecological. The mangroves of our own tropical 

 coasts have not been given as much attention as these plants might 

 deserve ; while the physiological relations have only in a few notable 

 instances been made the subject of detailed study. The most ex- 

 tensive work has perhaps been done at the Buitenzorg Botanical 

 Garden in Java by Haberlandt, etc. 



In South Florida, although :he climate is not like that of Java, 

 the facilities afforded for study of mangroves is fairly good, but 

 a great handicap has been found in the pursuit of this research, 

 viz., that owing to the character of the soil and other considerations 

 there are no mangroves in the Dry Tortugas and all the material 

 had to be brought from the Lower Florida Keys with a consequent 

 loss of many seedlings. Other studies which would have been 

 made, particularly on the embryology of Rhicophora, have been 

 deferred for the present until a tropical laboratory can be secured, 

 where the plants can be secured conveniently, quickly and in 

 abundance. 



During the summer season of 1916 fortune favored the work 

 at Tortugas in as much as seedlings were found in considerable 

 quantity on the beaches of the islands composing the group. These 

 viviparous seedlings had been drifted westward from the Marquesas 



1 Bowman, H. H. M., Carnegie Institution Year Books, 1915, p. 200; 1916, 

 pp. 188-192. 



