VOL. I.] Plants of Santa Catalina Island. ae 
RHUS INTEGRIFOLIA B.&H. Mr. Lyon mentions a peculiar 
ternate-leaved form. The ternate leaves are usually scattered among 
those of the usual shape, and no bush with any large proportion of 
the abnormal ones was seen (PI. iv, figs. 3-7). 
RHUS LAURINA Nutt. The leaves of this species occasionally 
show a tendency to become pinnately divided. The abundance of 
Rhus is noticeable. 
HOSACKIA GLABRA Torr. Growing usually in the slender clus- 
tered form of the main-land, but sometimes with a considerable 
elongation of the woody base, when it becomes \S. dendroideum 
Greene. 
PRUNUS ILICIFOLIUS Walp. Mr. Lyon’s list gives also P. occi- 
dentalis Nutt., but both forms must belong to the same species, and 
“ Nutt.’ is probably a misprint for Swartz,* who described a Prunus 
occidentalis from the West Indies. The leaves are usually more 
entire than the Santa Cruz Island forms. Curiously enough the 
island form, with longer, more pointed and less dentate leaves, is 
found in the cafions of the mountains of Baja California. 
HETEROMELES ARBUTIFOLIA Reem. Common and often form- 
ing groves in the manner of Lyonothamnus. 
LYONOTHAMNUS FLORIBUNDUS Gray. This remarkable plant, 
described by Dr. Gray from specimens collected in the northwestern 
part of the island and dedicated to its discoverer, furnishes a nota- 
ble illustration of the variation of leaves. In the groves first seen 
they were long, slender and usually entire, but near the head of 
Swain’s Cafion two groves of considerable extent are found, the 
lower one of which furnishes divided as well as entire leaves (Pl. v, 
figs. 1-7). These approach far too nearly ZL. asplenifolius Greene 
(figs. 8-13) from Santa Cruz and Santa Rosa islands, which was 
separated from the first on the form of the leaves alone. They dif- 
fer in no respect in flower or fruit, grow alike in groves upon the 
slopes of cafions, have the same form, the same pubescence, the 
same shreddy bark, and the stipules which Dr. Gray supposed to 
- be better developed in L. asplentfolius prove to be equally so in the 
first, and now the connecting forms of leaves make it certain that 
they are but variations of a single species. It would be as reason- 
able to consider a bush of Rhus integrifolia, with ternate leaves, a 
distinct species as to give that rank to the Santa Cruz Lyonotham- 
*Prod. Fl. Ind, Occ., 80. 
