292 CONTRIBUTIONS FBOM THE NATIONAL HERBARIUM. 



the houses face the single street, which is several miles long. The 

 elevation of the town is a little over 1,800 meters, but the moun- 

 tains come down to its edge, and one of the near-by peaks, called the 

 Bufa, rises to an elevation of nearly 2,400 meters. At the time of 

 my visit the town was in a deplorable condition of decay, hundreds 

 of people having departed to other localities. 



I had long been anxious to visit that locality, as it was the place 

 where Dr. A. Wislizenus was held a prisoner during the Mexican war 

 and where he collected many new species. I went especially to 

 re-collect his Cactaceae, of which Dr. George Engelmann had de- 

 scribed six species. The cactus flora was very scant, but all the 

 species were collected, although in most cases only a single specimen 

 was found. The forest vegetation has doubtless changed very much 

 since Wislizenus's time, for the pines, of which he found three new 

 species, have nearly all disappeared and the mountains are nearly 

 treeless. Along the stream which runs through the town are still 

 some large poplars. 



On April 4, accompanied by Dr. E. Palmer, I took the train at 

 Chihuahua City and proceeded up into the Santa Eulalia Mountains, 

 some 10 miles east of Chihuahua City. In these mountains consid- 

 erable silver ore is mined, and at the time of our visit work was 

 being actively prosecuted. Only one day was spent here, but many 

 interesting Cactaceae were examined, some of which proved to be 

 undescribed. A few weeks later Doctor Palmer returned to Santa 

 Eulalia and made an extensive collection. In 1888 these mountains 

 were widely explored by Dr. C. G. Pringle, who brought out of them 

 many new species. 



Several days were spent at El Paso and Juarez. Several excur- 

 sions were made into the Franklin Mountains and a day was given 

 to exploring the low hills in Chihuahua southwest of El Paso. On 

 this day I had the assistance of Prof. Elmer Stearns and his botanical 

 students, some thirty in all, of the Agricultural College at Juarez. 

 These Mexican boys were greatly interested in my work and brought 

 in many cactus specimens. In 1907 I had made a previous visit to 

 El Paso and during these two short trips some forty numbers were 

 collected. 



These places were especially interesting as being the type localities 

 of many of the species collected by some of the older explorers. Of 

 these species were obtained Echinocereus stramineus Engelm. and 

 Populus wislizeni Sargent. 



On the morning of April 29 Doctor MacDougal took me in an 

 automobile from Tucson to Nogales on the international boundary. 

 The next day we collected various Cactaceae and some other plants, 

 and also obtained some fine photographs both of the landscape and 

 of individual plants. (Plates 46, 47.) 



