138 The Nardoo Plant 



reasons which induce me to regard the opinions advanced by 

 Dr. Hanstein and his literary predecessors on the limitations of 

 the Marsilea species as untenable. Dr. Hanstein, after refer- 

 ring to the touching incidents, under which after their heroic 

 exploit Bourke, Wills, and King endeavoured to maintain 

 their sustenance on the Marsilea fruit or nardoo, gives an 

 accurate description of certain specimens of this fruit which 

 he received from Dr. Richhard Schomburgk, of Buchesfelde, 

 South Australia, and describes the species as a new one under 

 the name of Marsilea, salvatrix, a designation which could 

 not have been nobler chosen if this species had real claims on 

 permanent distinction. 



All plants of a wide geographical range, adapting them- 

 selves to . many varied influences both of climate and soil, 

 undergo proportionate variations, and there are probably no 

 other tracts of the globe where the power of nature to adapt 

 its vegetable productions to varied conditions can be more 

 instructively studied than in this country. We possess glacier 

 regions, moist jungle forest, and draught-exposed desert tracts 

 at some spots in close proximity, and again, in some instances, 

 the transit of one of these geographical features to the other 

 and therewith the change of generally diffused species of 

 plants into marked varieties are sudden in the extreme. 



In phytological journeys, which under the favour of cir- 

 cumstances it fell to my share to perform to a wide extent, 

 both over the northern and southern regions of Australia, 

 and equally over our snow}^ highlands and the low depres- 

 sions of the interior, I enjoyed frequent opportunities of 

 tracing the cyeles of forms, which many of the widely 

 spread plants of this country are apt to assume, often won- 

 derfully discrepant in their external appearance, and yet 

 so closely interchained by intermediate links as to afford some 

 of the strongest proofs against the doctrine of the mutability 

 of species. 



The Marsilea, although not a child of colder regions, and 

 hence not ascending to our alpine elevations, is otherwise so 

 extensively distributed as to afford a striking instance of the 

 fallacy to construct species on trifling exterior characters. We 

 may in Australia observe this plant as well in the waters of the 

 tropical coast forests, as in and around swamps, lakes, and 

 lagoons of the otherwise dry interior tracts. In depressions 

 of the latter, subject to periodical inundations, it grows often 

 very gregariously, and there it is also where, after the recess 

 of the water the fruit is so copiously developed as to render 



