GARDEN FLOWERS. 299 



Many of the above are not hardy, and there are some 

 thirty other still more tender species. 



Plataxthera. [Orchidaceae.] A family of orchids, 

 mostly hardy, formerly known as Orchis. Soil, peat, gener- 

 ally moist. All these plants are of difficult culture. The 

 species are P. obtusata, rotundifolia, o?'bicuiata, Hookerii^ brac- 

 teata,'hyperborea, dilatata^flava, cristata, ciliaris, bkpharigloftis, 

 leucophcea, lacera, psycodes, Jimb?'iata, and peratnoena ; all na- 

 tives of North America. The flo^vers are very handsome. 



Platanus. Plane-tree. [Platanaceae.] Hardy deciduous 

 ornamental trees. Soil, deep loam. Propagated by seeds, 

 cuttings, and layers. 



P. Occidentalis (y^ts,i&rn) ; 70 feet ; North America ; 1636. P. 

 aurea variegata (golden-variegated-leaved); 70 feet ; 1846. P. 

 integrzfolia {Q.nt\re.-\Q.2i\Q.dL) ; 70 feet; 1845. P. heterophyllaiyz.- 

 rious-leaved) ; America; 1842. P. Orietitalis (Eastern); 50 

 feet; Levant; 1548. /*. <2i:^rz/6'//d; (maple-leaved) ; 70 feet ; Le- 

 vant. P.cuneata (wedge-leaved); 20 feet; Levant; 1739. P- 

 Hispaiiica (Spanish) ; 70 feet ; Spain. P. laciniata (cut-leaved); 

 70 feet ; 1845. P- mo7istrosa (monstrous) ; 70 feet ; 1845. 



The European species are somewhat tender. 



.Platycodon. [Campanulaceae.] Hardy herbaceous per- 

 ennials. Propagated by seeds and division in the spring, 

 and by cuttings in the summer. Soil, sandy loam. 



P. gratidifioriun (large-flowered) ; hardy perennial ; i foot ; 

 flowers blue, in June ; Dahuria ; 1782. Variety tz/^^^, from China, 

 has white flowers ; variety alba plena has semi-double flowers. 



These plants are half-hardy in the Northern States. 



Platystemon. [Papaveraceae.] Pretty annuals, of pros- 

 trate habit. They like a cool situation, and a peaty soil, 

 but will grow in any rich light earth. Sow about the middle 

 of May. 



P. Californicum (Californian) ; hardy annual ; i foot ; flowers 

 sulphur-yellow, in June; California; 1823. 



