VOL. I.] Naturalized Plants. 183 
specimen of this beautiful little grass was for a long time a rare event 
in my herborizings. But year by year it has become more abun- 
dant until it is now common throughout the San Bernardino Valley 
and the surrounding foothills. It is equally abundant in the vicin- 
ity of Los Angeles, and is also said to grow in San Diego County. 
Three European species of the genus Bromus are of very recent 
introduction in this region. &. mo//is has been sent me by Dr. H. 
E. Hasse, who collected it in May of the present year at Santa 
Monica, under conditions which made evident its recent intrusion. 
There is no record of its having been found previously in the State. 
B. maximus had been collected at San Francisco, and B&B. ru- 
dens in Plumas County at the time Dr. Thurber elaborated the 
grasses of California,* and these two stations remain the only ones 
published. It is doubtful, however, if either species was as scarce 
as this scanty record would indicate. In my own neighborhood 
both have made their appearance very recently. 2B. maximus was 
first observed only two springs ago near Governor Waterman’s res- 
idence in the foothills north of San Bernardino. There were some 
two or three hundred plants, scattered along the roadside and 
through an adjoining field of grain, no more than might easily have 
been the progeny of a single individual of the year before. In the 
two succeeding years it has become quite abundant by the roadside 
for a mile up the cafion. During the present spring a few plants of 
this grass have been seen in two places near the town of San Ber- 
nardino, more than six miles from the first station. Bromus rubens 
first appeared the same year in Reché Cafion, on the opposite side 
of the San Bernardino Valley, and also by the roadside. It like- 
wise has multiplied abundantly and has spread itself about the same 
distance up this cafion. It is a curious circumstance that in both 
these instances the plants have spread for a long distance up, and 
not at all down the cafions, but it is not easy to assign a cause for 
this peculiarity. All three of these bromes were probably intro- 
duced in foul seed grain. It may not be out of place to mention 
here a fourth species of this genus which has established itself a 
little outside of the limits to which these notes are properly con- 
fined, and which is of some interest as it has not heretofore been 
detected in the United States. This is B. Madritensis, and like the 
“Bot, Cal, Hs.” 
