500 Drs. Will and Fresenius on the 



have yet been identified. M. Quoy, however, assured M. de Blain- 

 ville that the bones in the Paris Museum which Cuvier supposed to 

 belong to the Dodo, were brought, not from Mauritius, but from 

 Rodriguez ; and it is therefore probable, as supposed by M. de Blain- 

 ville, that they may have belonged to the Solitaire of Leguat. There 

 are, too, certain bones from Rodriguez presented by Mr. Telfair to 

 this Society (Zool. Proceedings, Part I. p. 81) ; and in the Ander- 

 sonian Museum at Glasgow there are also some so-called " Dodo's 

 bones from Mauritius." All these materials should be submitted to 

 careful examination ; and we may feel confident that if Prof. Owen, 

 who has so skilfully demonstrated the affinities of the Dinornis from 

 a few fragments of the skeleton, were to take these materials in hand, 

 he would soon deduce some valuable results, whether positive or 

 negative, from the investigation. 



Much light also might probably be thrown on the subject if natu- 

 ralists residing in Mauritius, Bourbon and Rodriguez would endea- 

 vour to obtain further evidence. The alluvia of streams, the soil on 

 the floors of caverns, and even the ancient mounds of rubbish near 

 towns and villages, should be carefully searched, and every fragment 

 of bone preserved. We may hope that the success which has at- 

 tended such researches in New Zealand will stimulate the naturalists 

 of Mauritius to similar eflforts, and that the Solitaires and Oiseaux 

 bleus will ere long, like the Dodo and the Dinornis, take their just 

 rank in our systems of ornithology. 



LXXXI. On the Inorga7iic Constituents of Plants. 

 By Drs. H. Will and R. Fresenius*. 

 CINCE the true value and importance of inorganic constitu- 

 *^ ents for the existence of plants has been pointed out and 

 established by Professor Liebig, it has become an object of 

 high. interest in vegetable physiology and agriculture, to pos- 

 sess an extended series of trustworthy analyses of the ashes 

 of different plants, and of different parts of plants, conducted 

 with reference to the points to which the Professor has di- 

 rected attention in his work, " Organic Chemistry in its appli- 

 cations to Agriculture and Physiology." We say trustworthy, 

 and thus specially directed analyses, since in those already at 

 command the requisite conditions are but partially supplied. 



To the exemplary labours of De Saussure concerning vege- 

 tation, is due the undisputed merit of having first incited to a 

 knowledge of the importance of the inorganic constituents of 

 plants; he established the fact by means of numerous analyses 

 of vegetable ashes. The methods of chemical analysis, and 

 especially of the quantitative estimation of the more important 

 constituents of vegetable ashes (phosphoric acid for example), 

 were not however at that time such as to render the results of 



* Communicated by the Chemical Society; having been read May 20, 

 1844. 



