COMPOSITE FAMILY 



rhyme showing this, belief is still extant among the common people 

 of England: 



Thou pretty herb of Venus tree 



Thy true name it is Yarrow; 

 Now who my dearest friend shall be 



Pray tell thou me to-morrow. 



DAHLIA 



Ddhlia varidbilis. Ddhlia rosea. 



Named in honor of Dr. Dahl, a pupil and friend of Linnjeus. 



Dahlia variabilis is believed to be the primitive form of all the Dahlias 

 in cultivation, with the possible exception of the Cactus Dahha, Dahlia 

 j'uarezii. Found at an elevation of seven thousand feet on the mountains 

 of Mexico. Extremely variable. 



Roots. — Tuberous, must be stored in winter and planted. 



Stem. — Four to six feet high. 



Leaves. — Pinnately compound; the leaflets lobed. 



Flower-heads. — Radiate; rays red, yellow, or white; disk-florets 

 yellow. By cultivation the disk-florets are turned into rays producing 

 the well-known double forms. 



Involucre. — Of several series of bracts; the outer series leafy, re- 

 flexed; inner series more or less scarious, close to the rays. 



Receptacle. — Convex, covered with involucral scales. 



The liorticultural history of the Dahlia is well known. The 

 plant was discovered by Cervantes, the director of the Mexican 

 Botanic Gardens, and by him sent to Spain late in the eighteenth 

 century. From this stock in 1789 specimens were brought into 

 England, but these all died. In 1800 a consignment of seeds and 

 tubers was sent directly to France from Mexico. The hope then was 

 that the plant would produce an edible tuber; which hope has been 

 disappointed. From this consignment specimens came into Eng- 

 land; these were successfully grown and by 1826 the Royal Hor- 

 ticultural Society reported sixty varieties cultivated upon its 

 grounds. There are probably in the present garden race shght 



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