APPENDIX 541 



The small seeds, or the seed-like nucules as in 

 Suseda, have but little floating power even after 

 prolonged drying. 



Glaux maritima 

 Flantago maritima 

 Samolus valerandi 

 Suada fruticosa 

 Sumda maritima 



Salicornia herbacea. Would be dispersed probably by floating portions 

 of the plant, which, however, soon break down and the liberated seeds 

 sink. The floating seedling thrives in sea-water and could be carried 

 great distances (see Note 19). 



Salsola kali. I experimented on this plant, both on the coast of 

 Devonshire and in Chile, with the same results in both localities whether in 

 the fresh state or after drying for weeks. The fruit sinks, but when the 

 plant dries the fruit is often detached inclosed in the perianth, and floats 

 in that condition in sea-water for a few days. Portions of the plant of 

 various sizes bearing mature fruits all sank within ten days. It would 

 seem at first sight, from the observations of Prof. Martins, that the fruits 

 float for several weeks ; but his experiments were mainly directed to 

 testing the powers of germination after sea-water immersion ; and it is 

 often not at all clear whether flotation is implied or even to be correctly 

 inferred. There is a slight suspicion of germination on the plant. Sea- 

 birds doubtless aid in the dispersion of this plant ; the dry crisp portions 

 of the plant carrying fruits catch readily in one's clothes on account of the 

 prickly-pointed leaves. 



Scirpus maritimus. The fresh fruits float a few weeks in sea-water in 

 most cases, but 10 per cent, remain afloat after two months. After 

 drying for some months 30 per cent, remain floating after two months' 

 immersion. 



The fruits float a few days or a week. Drying 



somewhat increases the buoyancy. Sir W. BuUer 

 • in New Zealand found in the gullet of Anas 



superciliosa, the Grey Duck, numbers of the fruits 



of Triglochin triandrum. 



Triglochin maritimum 

 Triglochin palustre 



NOTE 18 (page 35) 



The Buoyancy of the Seeds or Fruits of the British Littoral 

 Plants that are confined to the Beach 



Arenaria (Honckeneya) peploides. The seeds float for many months in 

 sea-water unharmed, 75 per cent, floating after a year. They never 

 germinate in sea-water; but on being transferred to fresh water after 

 many months in sea-water they germinate healthily in a few days. These 

 seeds only float a few days in fresh water, all sinking within 10 days, and 

 even after a year's drying they sink in a week or two. Precisely the same 



