132 MISSOURI BOTANICAL GARDEN, 
tion was issued by Engelmann and Gray as Plantae Lind- 
heimerianae,* Part I, in 1845, while the collections of 1845 to 
1848 were in part described in 1850 as Part II of the same. 
The collaboration of Engelmann and Gray in this publication 
led to a life-long friendship between them and proved of the 
greatest advantage to both in the prosecution of their scien- 
tific work. Gray with his larger herbarium and library did 
many of the critical determinations for Engelmann, while the 
latter kept more in touch with the various exploring expedi- 
tions, which made St. Louis their outfitting point, and sup- 
plied many of the field botanists to accompany them, and 
his critical studies in some of the most difficult genera are 
still regarded as classics in botany. Indeed the influence of 
Engelmann in the study of the flora of the Middle West is 
marked and the great work done in America by the German 
botanists of the last century deserves more than passing 
notice. 
No one can do much in systematic botany in America with- 
out soon becoming acquainted with the names of Engelmann, 
Lindheimer, Geyer, Fendler, Wislizenus, Gattinger, Hilgard, 
Liiders, Riehl, Rugel, Eggert and a host of others of German 
origin. Many of these, like Engelmann and Lindheimer, 
were trained in the German universities and came to America 
to secure the freedom denied them in their native land. 
Others, as Maximilian and Roemer, simply made scientific 
expeditions into unexplored regions of the United States and 
published the results of their work on their return to Germany, 
while many others devoted their spare moments to botany 
through mere love of Nature, without intention of publica- 
tion or hope of reward, and it was these that turned to Engel- 
mann for encouragement and assistance in their work. Geyer, 
Fendler and Lindheimer did practically all their work in co- 
operation with Engelmann, while many other botanists of 
German descent looked to him for assistance in their botanical 
* Plantae Lindheimerianae, Part I, was issued about Sept. 23, 1845 
and Part II about May 27, 1850, as shown by Gray’s unpublished letters 
to Engelmann: the names given in part I therefore antedate those of 
Scheele in vols. 21 and 22 of Linnaea and in Part II all those of Scheele 
subsequently published. 
