154 



Report on Botany. 



1st. The translation, for the Transactions of the New 

 York State Agricultural Society, of Dr. Fisher's Contribu- 

 tion to the Biology and History of the Development of the 

 Ustilagineos, makes this work available to those who are 

 conversant with the English language only. The species 

 of Ustilago, are somewhat numerous and two of them, U. 

 Carbo and U. Maydis, are especially injurious to our crops 

 of grain and Indian corn. It is this power they have to 

 affect us in our material interests that causes the most 

 practical as well as the scientific mind, to hail with satis- 

 faction every new acquisition of knowledge concerning 

 these parasites, every new discovery that tends to bring 

 them under our control. From Dr. Fisher's contribution 

 we learn that he was able in some cases to trace the my- 

 celium of the parasite in and through the tissues of the 

 supporting plant from its earliest growth up to the time 

 and place of the spore formation. It was found, even in 

 parts of the supporting plant, beneath the surface of the 

 ground, although the spores of the parasite are never pro- 

 duced in such parts. Hence the conclusion is that the 

 parasite enters its host plant at a very early period of its 

 existence. But how it enters, just when and under what 

 conditions, is a problem yet to be solved, and upon the 

 solution of it would seem to depend the intelligent applica- 

 tion of a remedy. If the germ of the parasite is in or upon 

 the seed of the supporting plant, ready to attack the sprout- 

 ing embryo and grow with its growth, we must take care 

 to plant only unaffected seed. If it requires peculiar condi- 

 tions for its development it is desirable that we understand 

 those conditions in order to avoid or counteract them. 



2d. Genera Lichenum, an arrangement of the North 

 American Lichens, by Prof. E. Tuckerman, is a valuable 

 repository of information in the department of botany of 

 which it treats. It not only discusses the arrangement of 

 the genera but also to some extent the grouping of species. 



