COMPOSITAE 639 



2. C. crispus L. In waste places: N. B. and N. S. and in ballast 

 about the seaports. Native of Europe. 



Rare as a weed near New York and Philadelphia. 

 C. acanthoides L. has been collected as a waif in Conn. 



55. Mariana Hill. 

 1. M. Mariana (L.) Hill. In ballast: eastern seaports. Native 

 of Europe. 



Rare as a weed near the vicinity of New York and Philadelphia. 



56. Onopordon [Vaill.] L. 



1. O. Acanthium L. In waste places: N. S. and Ont. to N. J. 



and Mich. Native also of Asia. 

 Rare as an occasional weed. 



57. Centaurea L. 



Bracts of the involucre lacerate or fimbriate, not spiny. 



Annual; pappus about the length of the achene. 1. C. cyanus. 



Perennials; pappus obsolete, or short. 



Bracts of the involucre laciniate or entire. 2. C. Jacea. 



Bracts of the involucre, or their tips, pectinate fringed. 



Lower bracts, pectinate-fringed to below the middle. 3. C. nigra. 

 Lower bracts pectinate-fringed only at the tips. 



Leaves entire, toothed on the lower bracts. 4. C. vochinensis. 



All but the upper leaves pinnatifid into linear 



segments. 5. C. maculosa. 



Bracts of the involucre tipped with stout, nearly simple spines. 6. C. Calcilrapi. 



i. C. Cyanus L. In waste places and escaped from gardens: 

 Que. to N. Y., Va., S. Dak. and Kan. Native of Europe. 

 Rare as a weed, often wanting. 



2. C. Jacea L. In waste places: N. Y. to Conn, and Vt., and in 



ballast about eastern seaports. Native of Europe. 



Not very common as a weed in most parts of our range, except 

 the pine-barrens. 



3. C. nigra L. In waste places and in fields: Newf. to Ont. and 



Pa. Native of Europe. 



Rare as a weed, more common near New York than elsewhere. 



4. C. vochinensis Bernh. Waste grounds: Ont. to S. N. Y. 



Native of Ga. 

 Rare as a weed. 



