478 A NATURALIST IN THE PACIFIC chap. 



also found in the Falkland Islands ; and Plantago maritima ; 

 besides a Chenopodiaceous plantjnot in fruit. The Plantago has 

 no capacity for dispersal by currents, and probably none of the 

 other plants are thus dispersed. I formed the opinion when in the 

 Straits that the beach plants on the Pacific and Atlantic coasts of 

 Patagonia could have but little communication by the currents, and 

 that they are in this respect quite cut off from each other. A 

 botanist who investigates the strand-flora of Patagonia and Tierra 

 del Fuego in connection with the littoral plants of the opposite 

 coasts ought, if he has not already done so, to obtain some very 

 interesting results from the standpoint of plant-dispersal. 



The northern limit of the plants of this zone near Coquimbo, in 

 lat. 30° S., is not determined by the change in climatic conditions 

 that goes normally with decrease in latitude, but by the vicinity of 

 the great deserts of Northern Chile, the aridity extending to 

 the beaches. 



Amongst the other plants occurring generally in the Convolvulus 

 soldanella zone of Southern Chile, species of Salicornia and Samolus 

 are to be observed in wet places. On the beaches near Valparaiso 

 and in the vicinity of Talcahuano there thrives a species of 

 Franseria, a Composite plant possessing prickly fruits well suited 

 for conveyance in bird's plumage, but not adapted, as shown in 

 Note 71, for dispersal by currents. Mesembryanthemum is a 

 typical beach-plant at Coquimbo, and an intruder from the 

 adjoining hill-slopes at Valparaiso. Raphanus, seemingly R. 

 maritimus, occurs in places, but apparently only as an intruder 

 from the cultivated districts behind the beaches. One or two 

 species of Euphorbia are not uncommon. A few small trees 

 or bushes of Acacia farnesiana grow typically on the beach at 

 Coronel and in neighbouring sandy tracts at Talcahuano, though 

 the plant, as Gay observes, has been introduced. Sophora tetrap- 

 tera, found also in New Zealand, and one of the most interesting 

 plants of the Antarctic flora, thrives as a small tree on the hill 

 slopes overlooking the harbour of Corral, becoming bushy where 

 in places it intrudes on the beaches, and fruiting there as freely 

 as on the slopes above. It was by testing the buoyancy of the 

 seeds of this plant that I was led to the discovery of its mode of 

 dispersal by the currents (I am indebted to Mr. Holland for the 

 specific determination of the fruits sent by me to the Kew 

 Museum). Other shore-plants, of course, occur in this zone ; 

 but I have gone far enough to illustrate the subject. Of the 

 numerous occasional intruders from the neisfhbourins inland 



