115 



largely taken the place of accumulation, as is attested by tlie 

 truncation of the 'Pleistocene-deposits, so that the Althorpes and 

 other adjacent islets have come to be severed from the main 

 mass. 



II. SKETCH OF THE BOTANICAL FEATURES. 



If my interpretation of the geological record be right, then 

 Southern Yorke-Peninsula was either a part of South'^rn Eyre- 

 Peninsula and Kangaroo Island or was brought in near proximity 

 by land extension from each area during the epoch of living 

 plant-species. Whilst the presence of the Great Salt-Marsh may 

 have proved a barrier to the migration of species of southern and 

 western origin in a northerly direction. But whatever explana- 

 tion is offered to account for the great floral contrasts between 

 these two portions of the Peninsula, the botanical differences are 

 so marked as to be a matter of jommon observation, and yet the 

 climatic and hydrographic conditions are absolutely the same on 

 either side of the Great Salt-Marsh. 



On the North side of the Great Salt-Swamp the country is a 

 savannah, timbered with Casuainna quadrivalvis and Melaleuca 

 2KtrvifoJia, and interspersed with small trees of Eucalyptus 

 odorata, Pittosjjorum jjJiillyrceoides and Acacia sclerophylla, whilst 

 the chief undershrubs are Bursaria spinosa and Myoporum 

 insidare. 



With the exception of the Warooka Ridge, the botany of 

 which resembles that of the country on the north side, most of 

 South Yorke-Peninsula is covered with a dense Mallee-Scrub, 

 here and there with open glades ; whilst on the exposed south- 

 east area the country is more heath-like, the shrubs being much 

 dwarfed. 



The chief constituents of the Mallee-Scrub are Eucalyptus 

 duimosa, E. uncinata, E. santaJifolia and E. goniocaJyx (this 

 genus is solely represented by these mallees, not a single speci- 

 men of a gum having been observed). Acacia anceps, A. calami- 

 folia and A. retinodes, Exocarpos spartea, Templetomia 7'etitsa, 

 Beyeria ojmca, Pimelea serpyllifolia, Eremopliila Bi'ownii, tfec. 



Many of the species of the scrub-lands are gregarious, both as 

 regards the smaller as well as the larger shrubs. 



The chief shrub of the marsh-lands is Melaleuca decussata, in- 

 terspersed amongst which are open areas clothed with Cladium 

 filum, whilst the slight elevated ground around and within carries 

 Casua7'ina quadrivalvis. Melaleuca pustidata forms dense thickets 

 around the salt lagoons. 



List of Species. — The total number of species observed is 235 ; 

 of these 41 are unrecorded for Yorke-Peninsula, and therefore are 

 restricted presumably to the Southern Section. Because of the 



