1908] Grinnell—Biota of the San Bernardino Mountains. 33 
Lilium Humboldtii Roezl & Leichtlin. 
The tiger lily was blooming in profusion in the upper portion 
of Mountain Home canon, July 22, 1907. 
Calochortus invenustus Greene. 
The mariposa lily was blooming abundantly in June along the 
upper Santa Ana. It occupied open spaces among the pines in 
the Transition zone, 6000 to 7500 feet altitude. 
Veratrum californicum Durand. 
The false hellebore was an abundant and conspicuous plant 
erowing in rank clumps two to five feet tall in the cienagas 
around Bluff lake at the head of the South fork of the Santa Ana, 
and Fish ereek, 7400 to 8500 feet altitude. (See pl. 14.) 
Yucca brevifolia Engelmann. 
The tree yucca was abundant, though not so large as I have 
seen it farther east near Hesperia, all along the desert base of 
the mountains. It extended up onto the ridges and alone the 
canons to as high as Cactus Flat, 6000 feet altitude, a hot pocket 
in which the yuccas were large and conspicuous over at least 
fifty acres. (Two other species of yuceas were noted on the desert 
slope. ) 
Populus Fremontii Watson. 
This Lower Sonoran species of cottonwood formed beautiful 
bright green groves wherever there were springs at the desert 
base of the mountains, 3600 to 4300 feet altitude. Cushenbury 
springs is refreshingly shaded by this tree. I saw several ex- 
amples below the mouth of Mill ereek at the Pacific base of the 
mountains, but I am quite sure that they had been purposely 
planted, as they have been about the town of San Bernardino. 
Populus trichocarpa Torrey & Gray. 
The black cottonwood was an abundant tree alone the canons 
of the Pacific slope of the mountains from the foothills up to 
6700 feet altitude on the upper Santa Ana. In the vicinity of 
Seven Oaks, 5000 feet, groves of large cottonwoods are an attrac- 
tive feature of the river bottom. 
