242 Dr Dauboii}' on the Writings and 



latter have already led, no less than by the researches of Bra- 

 connot and others, which have lately been instituted with 

 reference to the same question. 



I must not conclude my remarks on these two treatises, 

 which, together taken, present ns more completely than any 

 other work of the kind, a statement of what is known respect- 

 ing the structure and functions of the vegetable kingdom, 

 without noticing those most useful appendices to either part, 

 in which our author has followed up his delineation of the ex- 

 plored regions of botany, with a series of acute and searching 

 questions calculated to point out to us also the terra incognita 

 of the science. 



A few of these may, indeed, have since been answered, but 

 the greater number remain still unresolved ; and I know not 

 where the young experimentalist can better go, in order to 

 learn in what direction his investigations may most profitably 

 be carried on, or to what authority the student may more fitly 

 appeal, in order to estimate the relative degrees of confidence 

 that deserve to be placed on the statements of physiological 

 writers, than to the questions alluded to, in which, as our au- 

 thor informs us, he has laid open to the world all the doubts, 

 all the suspicions, all the schemes of research, which hehad har- 

 boured in his mind, originally with a view merely to his own 

 guidance and instruction in the scientific labours which he 

 had proposed to undertake, but which he was now compelled, 

 from the pressure of other engagements, to abandon to younger 

 men. 



It was previously to the publication of this work, namely, 

 in the year 1830, that I had the advantage, during a residence 

 of many months at Geneva, of hearing the principal points of 

 theory which are therein embodied set forth in the course of 

 lectures which their author annually delivered before the aca- 

 demy ; and although his fellow-citizen, who lias written a 

 brief sketch of his life and writings in the " Federal news- 

 paper," is mistaken in attributing my subsequent success in 

 gaining the professorship of botany in this imiversity to the 

 certificate of capacity for that office which the professor was 

 so obliging as to send to me when the vacancy occurred, as, 

 in point of fact, the election had taken place before its arrival ; 



