GEOKGE ENGELMANN. 521 



on the Gila ( Cerens giganteus) and an allied species ; by his synop- 

 sis of the Cactaceic of the United States, published in the Proceed- 

 ings of the American Academy of Arts and Sciences, 1856; and by 

 his two illustrated memoirs upon the Southern and Western species, 

 one contributed to the fourth volume of the series of Pacific Raih'oad 

 Expedition Reports, the other to Emory's Report on the Mexican 

 Boundary Survey. He had made large preparations for a greatly 

 needed revision of at least the North American Cactacece. But, 

 although his collections and sketches will be indispensable to the 

 future monographer, very much knowledge of this difficult group of 

 plants is lost by his death. 



Upon two other peculiarly American groups of plants, very difficult 

 of elucidation in herbarium specimens, Yucca and Agave, Dr. Engel- 

 mann may be said to have brought his work up to the time. Nothing 

 of importance is yet to be added to what he modestly styles " Notes 

 on the Genus Tacca" published in the third volume of the Transac- 

 tions 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 handling, 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 specimens). Euphorbia (in the fourth volume of the 

 Pacific Railroad Reports, and in the Botany of the Mexican Boundary), 

 Sagittaria and its allies, CaUitriche, Isoetes (of which his final revision 

 is probably ready for publication), and the North American Loran- 

 thacece, 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 Ameri- 

 can 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 American Vines, of which he at length recognized and 

 characterized a dozen species, — excellent subjects for his nice dis- 

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

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



