SCIENTIFIC AND POPULAB. 279 



a. P. tithjmaloides Poit. West Indies and S. America. Jew- 

 bush, Slipper-plant, Slipper Spurge. Plant emelic, antisyphili- 

 tic. 



1625. PEGANUM, L. Peganum. Zygopliyllareae. 



The Ureek nan)e of Rue, "solid'', alluding lo the fleshy 

 leaves. Odorous herbs. About 5 species, warmer regions of 

 New and Old World; 1 in U. S. 



1526. PELARGONIUM, L'Her. Geranium. Geraniaceae. 



From It reek, "siork plant", the beaked capsules reseuibling 

 a stork's bill. lierb.s or shrubs with umbellate flowers. About 

 400 species, Old World, mostly African. 



a. P. odoratissimiim Ait. South Africa. Nutmeg-scented Pelar- 

 gonium or Geranium. Leavts yield a fragrant volatile oil often 

 substituted J or oil of rose. From (b) P. radula (Cav. ) Ait., 

 Rough Rose Geranium, and (c) P. capitattiiu (L. ) Ait., Eose- 

 scemed Pelargonium or Geranium, similar oils are obtained, 

 known as oil of Rose Geranium or oil of Pelargonium. See 

 Andropogon. 



d. P. triste Ait. S. Africa. Night-scented Pelargonium. Tubers 

 edible. Among the numerous cultivated Pelargoniums may be 

 especially noted (e) P. graudiflorum Willd., the large- flowered 

 Lady Washingi on Geranium, ( f ) P. peltiitliill Ait. , ivy-leaved 

 Geranium and (g) P. zonale L'lier., the Common Horse- 

 shoe Geranium. 



1527. PELLAEA, Link. Cliflf-Brake. Poljpodiaceae. 



From Greek, ''dark", alluding to the stipes. Syn. Fleris, in 

 part. Rock-loving ferns. About 55 speiies; ]5 in U. S. (a) 

 P, atropiirpiirea (L. ) Link. (Pter. atrof.urpurea L. ). Brit- 

 ish America, south to Georgia and Arizona. Purple-stemmed 

 Clift-brake, Clayton's Cliti-brake, Indian' s-dream. 



1528. PELTANDRA, Raf. Arrow- Arum. Arac<'ae. 

 From Greek, "tshield stamen". Syn. Calla, Arum, Xantho- 



soma, in part, hog herbs with arrow-shaped leaves. Two 

 species, both of eastern U. S. 



a. P. sag-ittaefolia (Michx. ) Morong (C. sagittaefolia Michx., P. 



alba Raf., X. sagittaefolia Chapm., not Schott. ). Virginia to 

 Ilorida. White Arrow-arum, Arrow-leaved Spoon-flower. 



b. P. Virginica (L. ) Kunth (A. Virginicum L. ). Arrow Arum, 



Green Arrow- arum, Virginia Wake- robin, Tuckahoe*. Mhi- 

 zonies acnd, abounding in starch, formerly used as food by the 

 Indians. 



1529. PELTIPHYLLLM,Engelm. Saxifragaceae. 



From Greek, "shield leaf". One species in U. S. 



1530. PENAEA, L. Pensea. Penaeaceae. 



Named for Pierre Pena, French botanist, ]6th Century. Un- 

 dershrubs. About 20 species, Africa. 



