BY A. A. HAMILTON. 489 



Several plants of the Half-berried Salt-bush, Atriplex semi- 

 baccata, R. Br., a prostrate twiggy perennial with an extensive 

 range, coastal and interior, within Australia — one of our best 

 natural fodder plants — were also noted in this station. In 

 common with most members of the family (Chenopodiaceae) 

 it is a halophyte, but is apparently able to procure a sufficient 

 quantity of salt from soils not classed as saline to satisfy its 

 craving for this condiment. At Hen and Chickens Bay it has 

 migrated a considerable distance across the dry plain, reaching 

 the station occupied by its relative Atriplex patula. 



Two alien Composites are established on the margin of the 

 salt plain at Homebush Bay. The Bushy Starwort, Aster subu- 

 latus Mich., a tough-stemmed herbaceous perennial indigenous 

 in the North American saltmarshes, has founded a colony among 

 the broken Salicornia tufts, its tall dense growth excluding the 

 surrounding herbage. Its confrere the Stinkwort, Inula grave- 

 olens Desf.. a somewhat woody stemmed annual from the 

 Mediterranean winch has shown an extraordinary aptitude for 

 aggressive colonisation in Australia, is unable to accompany the 

 Starwort on to the salt plain, the soil salinity acting as a barrier 

 to its progress. The parachute crowned fruits of the Starwort 

 are held aloft on tall waving stems, the slender achenes are ex- 

 tremely light, and the pappus, which clings tenaciously, is rela- 

 tively large, a series of factors favourable to wind transport . 

 The fruits of both Composites sank within 24 hours, those of 

 the Stinkwort emitting a slight mucus. 



in the pools and shallow channels on the salt plain Ruppia 

 maritima L., common in most temperate and subtropical regions, 

 spreads a filamentous network, frequently occupying the whole 

 of the space in which the water is sufficiently deep to permit 

 the flotation of its thread-like stems. The occurrence of a 

 Ruppia lagoon at Deewhy is noted by Hedley (18, p. 53) who 

 presents a photo of the lagoon and offers some interesting ob- 

 servations on the range of heat and salinity imposed upon its 

 occupants. The Ruppia prefers still water, usually occupying 

 isolated pools and disconnected channels, but can withstand a 

 moderate tidal invasion. [A series of Salicornia-vncireled 

 Ruppia pools occurs on the barren salt plain at Homebush Bay 

 near Concord "West railway station (Plate xx., fig. 7).] At 

 Cook's River, near Tempo, a dense growth of Ruppia (Plate 

 xxi., fig. 10) permeates the waters of a channel connected with 



