viii PREFACE TO PART VII. 



nish. Should any improvement upon our method of treatment occur 

 to any of our readers, whereby the sections might be rendered tougher 

 without being discolored, we would (in behalf of all who study our 

 wood-sections, as well as ourselves,) be greatly obliged for -the infor- 

 mation. We desire it especially in connection with our further experi- 

 ments on the Palms, in which the fibro-vascular bundles are strong 

 and hard and the intervening parenchymatous tissue is very delicate. 

 It would seem as if some chemical treatment might toughen the 

 weaker tissue, but that is^ a question which we will have to leave to 

 sonie well-disposed chemist to answer. 

 LOWVILLE, N". Y., Oct. 25, 1897. 



