368 M. Balbiani on the Reproduction of the Aphides. 



insects. It is true that in a subsequent memoir, published ten 

 months after his first notice (December 1866) and six months 

 after my various communications to the Academy of Sciences 

 upon the same subject, M. Mecznikow gives a more detailed 

 description of them, and corrects some of his previous observa- 

 tions; but it is difficult to admit that in the interval he was 

 unacquainted with my investigations, published in June 1866 

 in the 'Comptes Rendus de FAcademie;' and yet no mention is 

 made of them in M. Mecznikow^s last memoir. M. Claparede, 

 who must excuse me for not having mentioned M. Mecznikow's 

 first publication, would have done an act of justice if he had 

 indicated that the latter observer had much less reason for not 

 citing a work which appeared six months before his own. 



As regards the reproach made to me by M. Claparede of 

 having introduced confusion into tiie language of histology, I 

 believe I have not in any way contributed to increase that which 

 already reigns in it, especially as to the definition, formerly so 

 clear and distinct, of the word cell. Notwithstanding the very 

 arbitrary acceptation that any one may now^-a-days give to this 

 term, I have not had the boldness to extend it so as to desig- 

 nate by it " whatever has a certain fo7'm," as I am accused of 

 doing by M. Claparede in his note. When I thought it pro- 

 per to give the name of cells to the histological elements which 

 I had before me, it was because I had ascertained the presence 

 in them of at least the two constituent parts now recognized as 

 strictly necessary to characterize a cell, in accordance with the 

 recent works of MM. Max Schultze, Briicke, Hackel, and others, 

 namely a nucleus and a protoplastic mass. M. Claparede, who 

 can see nothing in them but globules, nowhere mentions 

 whether he has endeavoured to enlighten himself by the em- 

 ployment of reagents ; and I have no doubt that a drop of 

 acetic acid would have done him more service than the objectives 

 of Smith and Beck, or the immersion lenses of Hartnack. 



I can only regret that my investigations have not received 

 the confirmation of an observer so distinguished as M. Cla- 

 parede, who has taken the trouble to test them. Perhaps the 

 fault may be that I have presented them with insufficient de- 

 tails, and especially that I have omitted to mention the means 

 that I employed for the determhiation of facts which, for the 

 most part, require minute and delicate observation. These are 

 defects which I shall endeavour to supply in a more circum- 

 stantial work on the same subject. 



