298 PLANTS NOVjE thurberian.e. 



Thurber's collections were still in New Mexico, it has unavoidably happened tha 

 Mr. Wright's name alone appears as the discoverer or collector of such novelties, in 

 the pages of the work above referred to. A full enumeration of the plants of Mr. 

 Thurber's collection would bring to view this priority in many instances, and would 

 show how largely he has subserved the interests of science by his extensive observa- 

 tions and collections, no small part of which were made under circumstances of great 

 privation and hardship. This is particularly the case in respect to the plants gath- 

 ered by him in the western part of Sonora, into which no other of our collectors had 

 penetrated, and on the Gila River and the Californian desert beyond its mouth, a region 

 which Colonel Emory and others had traversed, plucking here and there a scanty speci- 

 men ; but in which no one except Mr. Thurber can be said to have botanized. Con- 

 sequently these districts will be found to have furnished the principal new genera 

 and species characterized in this communication. Figures of the most remarkable of 

 these plants are in preparation: these it is thought best should be published in 

 Colonel Emory's final report, along with other illustrations of the botany of our Mexi- 

 can boundary, elaborated from the ample store of materials to which various col- 

 lectors have from time to time contributed. Meanwhile, as this extended report is 

 not likely to be completed and published for some time, I have the privilege of 

 making known to the scientific world the following new genera and species, which I 

 have been able to examine and to characterize. 



To give some idea of the geographical situation, features, and characteristic vegeta- 

 tion of the region in which these plants were collected, Mr. Thurber has, at my re- 

 quest, furnished a series of brief notes, which are subjoined; and to which I have 

 appended a few botanical remarks in the form of foot-notes. 



" The route from Eastern Texas to the Rio Grande was traversed in the months of 

 October and November, a season affording little of interest to the botanist. 



"The winter of 1850 and 1851 was passed at El Paso, or more properly at 

 Magoffinsville, a new settlement upon the ' American ' side of the river and oppo- 

 site the Mexican town. The latitude of this place is 31° 46' 5" and its elevation 

 above the sea level about 3,800 feet. During the winter, vegetation was completely 

 suspended; snow, ice, and sleet were frequent, and upon one occasion the mercury 

 fell to 2° Eahr. The first indications of returning spring were seen early in March, in 

 the sheltered ravines of the neighboring mountains, where Rutosma Texanum, Draba 

 micrantha, (Enothera chamcenerioides, and (E. pritniveris were collected ; and a little later 



