M. Duchartre on the Organogeny of the Malvacese. 247 



manner as they appear subsequently. The ovaries were from the 

 first grouped and adherent together, nearly in the same manner 

 as the flower subsequently exhibits them, their styles being di- 

 stinct at the summit, coherent in the rest of their extent, which 

 has been more slowly developed. As regards the peculiar results 

 to be deduced from these obsei-vations relative to the symmetry 

 of the flower of the MalvacecB, we have noticed them above, and 

 it would be useless to repeat them. 



Undoubtedly we have not been able ourselves to verify all these 

 facts, for this would occupy almost as much time as that devoted 

 by the author to the original investigations ; but we have verified 

 a sufficient number to justify the truth of most of them. We 

 regret that M. Duchartre has not carried out his extensive re- 

 searches still further, so as to teach us by anatomical details the 

 formation of the tissues in the organs, the external forms of which 

 he describes, and informing us at what periods the developments 

 he describes correspond to the changes gradually established in 

 the tissues, which are at first entirely cellular. 



We think that these details would throw a new light upon the 

 phsenomena of duplication, which are still so obscure, and would 

 enable us better to comprehend the mechanism of this substitu- 

 tion of several fascicled organs for a single plane organ. The for- 

 mation of cavities by an excavation in the centre of a cellular mass, 

 which assimilates certain carpels closely to anthers, is a fact so 

 much opposed to the generally admitted theories as to require 

 new observations and more development, especially by connecting 

 with it the histoiy of the ovule, and ascertaining how it is formed 

 in the cavities thus produced. 



We acknowledge that these are researches of extreme delicacy, 

 since the point at which M. Duchartre has arrived presented in- 

 contestable difficulties, and the dissection of such minute bodies 

 is exceedingly tedious, and even sometimes appears impossible. 

 But for some years we have seen that microscopic observation 

 surmounts difficulties which had long been considered insur- 

 mountable, and facts, the direct knowledge of which had been 

 despaired of, have become familiar to all those who are occupied 

 in this kind of researches : just as those parts of the earth which 

 were long unknown, now, being frequented, have become easily 

 accessible, and from them we set out for more remote unexplored 

 parts. These reflections must not be looked upon as detracting 

 from M. Duchartre^s investigations, but rather as an encourage- 

 ment for pursuing them. We address them to him the less re- 

 luctantly, because what he has already done proves what he is 

 capable of doing. 



