NATIVE AND GARDEN DELPHINIUMS OF 

 NORTH AMERICA. 



K. C. DAVIS. 



The name Delphinium (Linn. Sp. PI. 530, 1753) is from the 

 Greek delphin^ a dolphin, from the resemblance of the flower, 

 The common name is LARK SPUR. 



It is a genus of beautiful, hardy plants, annual or perennial, 

 erect, branching herbs. Leaves palmately lobed or divided ; 

 large, irregular, showy flowers in a raceme or panicle ; sepals 

 petal-like, five, the posterior one prolonged into a spur ; petals 

 two or four, small, the two posterior ones usually spurred, the 

 lateral or lower ones small if present ; the few carpels always 

 sessile, forming many-seeded follicles. 



There are probably more than 200 species. In fact Huth's 

 last complete monograph recognized 198 species besides a num- 

 ber of doubtful ones. The following treatment includes the 

 native and cultivated Delphiniums of North America, 52 

 species and many varieties and garden forms. Thirty species 

 are native of America north of Mexico, thirteen of which are 

 used in gardens. Thirteen Old World species have been intro- 

 duced int6 the American trade. Nine Mexican species are dis- 

 tinct, and none of them are in use. The mark (f) after a de- 

 scription indicates which plants are not used in the trade. 

 Four species are of much greater popularity than the others : 

 the annual D. Ajacis, and the perennials D. grandiflorum, D. 

 hybridum, and D. formosum. The last three have been es- 

 specially prolific in giving us new garden forms. 



In presenting this paper I wish to extend thanks to those 

 who have materially helped me, especially to those who have 

 freely given me the privilege of examining numerous speci- 

 mens : Dr. J. N. Rose, Professor E. L. Greene, Dr. N. L. 

 Britton and Dr. B. L. Robinson. 



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