136 
PII ARM AC AL PLANTS AND THEIR CULTURE. 
675. Polyporus species. Bracket or shelf fungi. Polyporiacece. 
Some of these fungi are eaten by Indians as well as by whites. They 
have but little food value, being entirely too woody. (Contrib. U. S. 
Nat. Herb. 7 : 300.) 
676. Polytrichum juniperinum. Hair cap moss. Robin’s eye. 
Bryoidece. 
This moss is said to be a powerful diuretic, useful in the treatment 
of dropsy. Other species of moss have similar properties, but are now 
but little employed by physicians. 
677. Populus species. Poplars. Salicacece. 
Cultivated as ornamental shade trees. The buds of P. balsamifera L. 
and of other species are highly balsamic, and have been used in kid- 
ney, pectoral and rheumatic complaints. The bark of several species 
(P. tremuloides and others) is used as a tonic remedy. (Am. Journ. 
Pharm. 226, 1892.) (Am. Journ. Pharm. 240, 1889.) (U. S. D.) 
678. Populus fremontii Wats. Fremont’s cottonwood. Salicacece. 
The Indians use a bark decoction as a wash for bruises and cuts, 
especially for the sores on horses caused by saddle chafing. 
679. Populus tremuloides Michx. American aspen. Salicacece. 
Indians use the bark of this tree in intermittent fevers. It is like- 
wise a popular domestic remedy, used as a tonic in fevers and malaria. 
The bark contains salicin and populin. (U. S. Geog. Surv. Wheeler’s 
Rep. Bot. 6 : 51 .) 
680. Porphyra laciniata Ag. Seaweed. Bangiacece. 
A seaweed of the Pacific Coast used as food by the Indians and 
Chinese. Rich in salt and mucilage. (Proc. Cal. Acad, of Sc. Bot. 2 : 
230, series 3). (U. S. Nat. Herb. 7 : 299.) 
681. Porphyra vulgaris Ag. Seaweed. Bangicece. 
Properties and uses like the preceding species. (Proc. A. Ph. A. 27 : 
134, 1879.) 
682. Portulaca oleracea L. Common purslane. Portulacacece. 
Common in low lands. Used medicinally by the Indians. Also en- 
joys an extensive popular medicinal use. 
683. Potentilla species. Cinquefoil. PosacecB. 
There are many California species, most of which are perhaps of no 
medicinal value. P. canadensis L. and P. argentea L. have been used 
as astringents in dysentery, chronic catarrh, night sweats, etc. The 
roots of P. sylvestris Neck (P. tormentill, Tormentilla potentilla, P. 
erecta) are rich in tannin, and are much used as an astringent remedy, 
and in tanning. They yield a red dye. These species are, however, 
not reported from the State. 
