VEGETATION OF MOUNT DIABLO. 169 
really more fertile summit. This will all be explained by the 
fact that the area of Mt. Diablo summit is only a small fraction 
of that of Mt. Hamilton. It is furthermore to be noted that, 
as there have been only some temporary I ts made at 
the top of Diablo, the number of introduced and foreign plants, 
—whose names considerable lengthened the Mt. Hamilton 
catalogue—is very small. Under the genial hospitality and 
with the assistance of Dr. Geo. Davidson and his party, who 
were there on Coast Survey work during June and July of 
1892, I found a day and a half quite enough time for cata- 
loguing somewhat thoroughly the anthophyte vegetation of all 
that which can be called the summit. The appended list will 
nevertheless fall short of completeness, as future explorations 
may well prove. 
LIST OF SPECIES. 
1. Laruyrvus vestrrus, Nutt; Torr. & Gray, Fl. i. 276. 
A depressed form with stems only a few inches long, occurring 
in stony ground at the summit. 
9. PsoraLea Oattrornica, Wats., Proc. Am. Acad. xii. 251. 
Very plentiful at the summit, on open stony ground; the root 
large, fusiform or variously branching. The species was 
known heretofore only from the head waters of the Salinas, 
and the present station becomes a very notable extension of 
its range. How the plant could have escaped the notice of 
the State Survey collectors, when on Mt. Diablo, it is difficult 
to conceive. 
3. Lotus numisTRatus, Greene, Pitt., ii. 139. 
4. Lorus ataper (Vogel), Greene, 1. ¢. 148. 
5. Lorvs orasstrontus, (Benth.), Greene, 1. ¢. 147, Fre- 
quent at the summit; more robust than on Mt. Hamilton. 
6. Trrronium Macrat, Hook. & Arn.; Bot. Mise. iii. 179. 
7. Trrrotim tTRIDENTATUM, Lindl. Bot. Reg., under t. 
1075 
