BY A. A. HAMILTON. "A<39 



the plants from a dry station on the marsh margin to the muddy 

 zone, their hahit also gradually developing from a prostrate to 

 an erect stature. Several forms of A. patula have heen de- 

 scribed as species, sub-species or varieties, but the evidence ob- 

 tainable in the local marshes points to a common origin, though 

 the resultant forms are dissimilar in leaf structure and habit of 

 growth. Further taxonomic references to halophytic plants will 

 be found in (3), (5), (14), (20). 



Seed Dispersal. 



Of the three principal agencies — apart from man — engaged in 

 seed distribution, viz., currents, birds, and winds, the former 

 plays the most important part in the local marshes, the newly- 

 formed mud-bank — the future saltmarsh — depending exclusively 

 upon water carriage for its afforestation by the mangroves. 

 Plants also occur whose fruits are embedded in the stems which 

 disintegrate and float on tide or current disseminating the seeds. 

 The capacity to germinate in salt water and float for a period 

 in the seedling stage — a special feature of the tropical man- 

 groves — is also characteristic of the seeds of several local species. 

 The large fruits with buoyant fibrous tissue, common in tropical 

 estuaries, are not found in the local marshes, the majority of the 

 plants producing small fruits or seeds with a brief flotation. The 

 albuminous seeds of the grasses and sedges are probably the 

 most tempting diet offered to visiting birds, fleshy baccate fruits 

 being conspicuously absent from our marshes; the insignificant 

 berries of the Sea-blite provide the best example of succulence 

 among the indigenous species. Plants were noted whose seeds 

 emitted a sticky mucus when wet, which would cause them to 

 adhere to the feathers of birds and facilitate their dispersal. 



Typical wind-dispersed seeds are the dust-like spores of the 

 lichens clothing the trunks of the Swamp Oak, which are launched 

 on their aerial flight from elevated positions. None of the in- 

 digenous marsh Composites are provided with wind-disseminat- 

 ing pappus, but several introduced members of this family are 

 dependent on their parachute of bristles for distribution. 

 Though the wind is less responsible for seed dispersal in our 

 marshes than either birds or currents, it enacts a beneficent roie 

 in pollination in this station, where insect life is infrequent, the 

 reeds and grasses, among herbs, and the swamp Oak, repre- 

 senting the arboreal species, relying upon the wind for this in- 



