GEORGE ENGELMANN. 445 



up to the time. Nothing of importance is yet to be added to 

 what he modestly styles " Notes on the Genus Yucca," pub- 

 lished in the third volume of the Transactions of the St. Louis 

 Academy, 1873, and not much to the " Notes on Agave," 

 illustrated by photographs, included in the same volume and 

 published in 1875. 



Less difficult as respects the material to work upon, but 

 well adapted for his painstaking, precise, and thorough hand- 

 ling, were such genera as Juncus (elaborately monographed 

 in the second volume of the Transactions of the St. Louis 

 Academy, and also exemplified in distributed sets of speci- 

 mens), Euphorbia (in the fourth volume of the Pacific Rail- 

 road Reports, and in the Botany of the Mexican Boundary), 

 Sagittaria and its allies, Callitriche, Isoetes (of which his 

 final revision is probably ready for publication), and the 

 North American Loranthacece, to which Sparganium, certain 

 groups of Gentiana, and some other genera, would have to 

 be added in any complete enumeration. Revisions of these 

 genera were also kindly contributed to Dr. Gray's Manual ; 

 and he was an important collaborator in several of the memoirs 

 of his surviving associate and friend. 



Of the highest interest, and among the best specimens of 

 Dr. Engelmann's botanical work, are his various papers upon 

 the American Oaks and the Coniferce, published in the 

 " Transactions of the St. Louis Academy," and elsewhere, the 

 results of long-continued and most conscientious study* The 

 same must be said of his persevering study of the North Amer- 

 ican Vines, of which he at length recognized and characterized 

 a dozen species, — excellent subjects for his nice discrimina- 

 tion, and now becoming of no small importance to grape- 

 growers, both in this country and in Europe. Nearly all that 

 we know scientifically of our species and forms of Vitis is 

 directly due to Dr. Engelmann's investigations. His first 

 separate publication upon them, " The Grape Vines of Mis- 

 souri," was published in 1860 ; his last, a reelaboration of 

 the American species, with figures of their seeds, is in the 

 third edition of the Bushberg Catalogue, published only a few 

 months ago. 



