THE BOTANY OF THE CUYAMACA MOUNTAINS, 93 
of this canon. A little rivulet still runs down here, but sinks be- 
fore reaching camp, and we had to obtain water from a well. Oak 
and sycamore (Platanus racemosa Nutt.) are here quite luxuriant 
close to the water but disappear below camp, and even willows be- 
come very small.* Remains of the ancient aqueduct, built by the 
Spanish missionaries full seventy years ago, to carry water from 
above this cañon nine miles to the mission, are very conspicuous, 
and show much engineering skill, as well as excellent workmanship. 
April 27th. Mr. Goodyear and Mr. Fox of the Southern Pacific 
R. R., walked up the cañon to examine the geology and the aque- 
duct, finding an excellent dam, which has withstood nearly a cen- 
tury of summer droughts and winter torrents. I rode up the south 
mésa nine miles to Cajon valley, a basin lying between the mésa 
and the hills, in part the remnant of an old lake-bed excavated by 
the river before it broke through the hills. It now however looks 
very arid, the granitic gravel covering it being only thinly con- 
cealed by crops of wheat just ripening, and the surrounding native 
vegetation being all dried up. A few small elder trees (Sambucus 
glauca) are the only green things visible about a spring on the 
south side of the yian. 
a The river runs on the north side, six ciil distant, and is there 
: — pretty well lined with the trees mentioned, together with some large 
cotton-wood poplars (P. monilifera). Its elevation being four 
hundred feet above the sea, and the impervious granite retaining 
the moisture, we find a great increase in tree growth compared with 
the lower region, but still confined to the moist river banks. The 
ey greater moisture is still further shown by the fact that although so 
| i arid, this is the first valley where a crop is successful this year, 
though it will mostlybe cut for hay, which is so high priced at 
San Diego as to make it more profitable to cut it than to wait for 
the uncertain and light crop of wheat. Some other grain and vege- 
tables are also raised along the river. The California wild grape 
- (Vitis Califbrnica Benth.) grows in moist spots about this valley. 
The green cornel (Cornus piena Nutt. ) also forms a small tree 
: along the streams. — 
-= About six miles east, the river’ again r a cañon in which it 
5 never dries up and where the Indians have their favorite settle- 
ment, convenient to the acorn crop. The road, areais leaves 
E E A S E er T 
* Two or three erpe in these mountains grow sixty f feet high and two in ape 
Ic 
