Pycnostachys 



( 251 ) 



Pyrethrum 



Principal Species : 



tanceolatum, sum., stems 

 downy. 



miitirum, 1' to IV, sum., 



wh., iu dense terminal 

 clusters. The whole 

 plant is aromatic (*.'/. 

 pilosum). 



PYCNOSTACHYS. 



Erect growing stove herbs (ord. Labiatie). Prop- 

 agation, by root division and by cuttings. Soil, 

 loam two parts, leaf mould one part, and sand. 



Principal Species : 

 coerulea, 12" to 1~>", Aug., urticnnfolia, 10', Dec., 



aim., hi. Feb., per., bl. 



botanists do not attach much importance to these 

 distinctions, and the two genera are now merged, 

 but the Pyrethrums have been kept distinct in this 

 work for cultural reasons. Perhaps no section of 

 hardy flowers is in greater favour than this, and it 

 will be long ere the name Pyrethrum is forgotten. 



The florists' varieties, for which see special list, 

 are all easy to grow in any good garden soil, 

 and they may be propagated by division. They 

 like best, however, to be allowed to remain un- 

 disturbed for two or three years, and then, if given 

 annual top-dressings of well-rotted yard dung, they 



tscil Company, Ltd. 



PVIIVS BACCATA (see p. 253). 



PYRALIDINA. 



A group of moths, containing the largest of thn 

 Microlepidoptera, and not infrequently like some 

 of the smaller Noctuas in appearance. They 

 very seldom do injury to garden produce, and are 

 of little importance. 



PYRETHRUM. 



Description. Correctly this genus of hardy 

 piTi'iinials belongs to the Chrysanthemums {aril. 

 Composite). Originally the Pyrethrums were 

 separated from the Chrysanthemums because of 

 the i iresenoe of a pappus in the shape of an elevated, 

 membranous border, and the fact that the achenes 

 (fruits) are angular, but not winged. Later 



flower superbly. By cutting off the first crop of 

 flowers early, and removing the flowering stems to 

 the base, a second crop of bloom may be obtained 

 in the early autumn, but to support the plants over 

 the double strain liberal supplies of liquid manure 

 should be given. Seeds are usually only employed 

 when new varieties are wanted. Tchihatchewii is 

 an invaluable plant for dry banks, and uiiginosum 

 is suited in the wild garden; it is generally rather 

 too coarse for the herbaceous border. 



The Golden Feather (Parthenium aureum) is 

 invariably treated as an annual, seed being sown in 

 heat under glass, in spring, the -re. llinus being 

 duly pricked out into boxes or pans to strengthen, 

 and transferred to the open ground about the end 



