186 FOEEST CULTURE AND 



lia, Zamia alone having been noticed in South Austra- 

 lia (Zamia MacdonneUii), but there as an exceedingly 

 local plant. ' Neither climate nor geologic considera- 

 tions explain this curious fact of phytogeography. 

 Over some of the healthy'tracts of scrub-country, to- 

 ward the south-west coast, poisonous species of Gas- 

 trolobium (Gastrol bilobum, G. oxylobioides, G. caly- 

 cinum, G. callistachys) are dispersed. These plants 

 have, in some localities, rendered the occupation of 

 country for pastoral pursuits impossible, but these 

 poison-plants are mostly confined to barren spots, and 

 it is not unlikely that, by repeated burnings, and by 

 the raising of perennial fodder-plants, they could be 

 suppressed, and finally extirpated. Fortunately, in 

 no other parts of Australia Gastrolobium occurs, ex- 

 cept on the inland tract from Attack Creek to the Sut- 

 tor River, where flocks must be guarded against ac- 

 cess to the scrub-patches harboring the only tropical 

 species (Gastrolobium grandiflorum). The deadly ef- 

 fect occasionally produced by Lotus Australis, a herb 

 with us of very wide distribution, and extending also 

 to New Caledonia, and the cerebral derangements 

 manifested by pasture animals, which feed on the Dar- 

 ling Elver pea (SwainsonaGreyana), need yef extensive 

 investigation, but may find their explanation in the 

 fact that the organic poisonous principle is only local- 

 ly, under conditions yet obscure, developed ; or in 

 the probable circumstance that, like in a few other 

 leguminous plants, the deleterious properties are 

 strongly concentrated in the seed. The gorgeous des- 

 ert-pea (Clianthus Dampierii), which, in its capricious 

 distribution, bftS beeu traced sparingly from the 

 I^acblan Biyef tP the north-west coast, offers stilj. tQ 

 fBpe^rCoUectQfs § J^lc^•ative gait). 



