SCIENTIFIC AND POPULAR. 297 



1627. PODOSTEMON, Michx. River-weed. Podostemaceae. 



From Greek, "foot stamen", the ovary being borne on a 

 slender stalk. Aquatic or paludal plants. About 20 species, 

 one in eastern U. S., viz. (a) P. Ceratopliyllum Michx., 

 River-weed, -Thread-foot. 



1G28. PODOSTIOMA, Ell. 1817. Podostigma. Asclepiadaceae. 



From Greek, ''stalked stigma". Syn. Stylandra, Nutt. 1818. 

 Perennial herb. One species, southeastern U. 8. 



1629. POGOOYNE, Benth. Pogogyne. Labiatae. 

 From Greek, "beard pistil". Aromatic low annuals. Five 



species, all of California. 



1630. POGONIA, Juss. Snake-mouth, etc. Orcliidaceae. 



From Greek, ''bearded". Syn. Arethusa, in part. Ter- 

 restrial orchids. About 30 species; 5 in U. S. 



a. P. ophiogrlossoides (L. ) Ker. Eastern U. S. to Canada. Rose 

 Pogonia, Adder's Pogonia, Snake-mouth, Adder's-mouth Po- 

 gonia or Orchis, (b) P.triautliophora (Sw. ) B. S.P . (P. peu- 

 dulaLindl.). Eastern U. S. Nodding Pogonia, Three-birds, 

 c. P. verticillata ( Willd. ) Xutt. Eastern U. 8. and Ontario. 

 Whorled Pogonia, Whorled Snake-mouth. 



1631. POGOSTEMON, Desf. Patchouli, etc. Labiatae. 

 From Greek, "bearded stamen". Herbs, some shrubby. 



About 35 species, East Indies to Japan. 



a. P. Heyneaniis Benth. (P. Patchouly Pelletier, P. suavis Ten- 

 ore). East Indies. Patchouli plant. Patchouli Balm. Vola- 

 tile oil distilled from the plant is Patchouli (Patchouly) or 

 Putcha-pat, much used in perfumery, 



1632. POINCIANA, L. (Poincea,Xeck.). Caesalpinaceae. 

 Highly ornamental trees . About 6 species, tropical regions, 



(a) P. regia Boj. Madagascar, planted for ornament in all 

 tropical countries. Royal Poinciana. 



1633. POLASISLi, Raf. Clammy-weed. Capparidaeeae. 



From Greek, "very unequal", referring to the stamens. 

 Syn. Cleome, Jacksonia, in part. Strongly scented herbs. 

 About 15 species, temperate and tropical regions; 4 in U. S. 



a. P. graveolens Raf. (C. graveolens Raf. (Kew. ), not L., C. 

 dodecandra Michx. ). British America, south to New York, 

 Kansas and Colorado. Clammy-weed, Worm-weed, False 

 Mustard. Plant acrid, counter-irritant, vermifuge. 



1634. POLEMONIUM, L. Greek Valerian, etc. Polemoiiiaceae. 



Latin name of \ alerian, of Greek origin. Herbs, mostly 

 perennial. About 20 species, north temperate zone; 16 in U.S., 

 mostly western. 



a. P. caeriileiim L. Europe. Greek Valerian, Jacob' s-ladder, 

 Ladder-to-heaven, Charity, Makebale; Ger. Speerkraut; Fr. 

 Val^riane grecque. Properties of (c). (b) P. Vau Briiu- 

 tiae Brit, of northeastern U. S., American Jacob' s-ladder, 

 closely resembles this species. 



