330 BOTANICAL GAZETTE [november 



correctly viewed by Fries, Koch, and other excellent botan- 

 ists, as mere varieties of this, the Common Dandelion." 2 At a 

 later date we find that Gray himself (Synopt. Fl. N. Amer. i 2 :44o. 

 1884) had come to regard all the continental North American 

 forms as representing varieties of but one species, which he stated 

 to be a "very polymorphous species." 



In 1907 there appeared the classic monograph of Taraxacum 

 by Handel-Mazzetti. This author, evidently impressed with 

 the desultory treatment which the genus usual ly had been accorded 

 in previous studies, quoted the relevant words of Reichenbach 

 (Fl. Germ. Excurs. 270. 1830-183 2), which are here translated: 

 "A genus seriously forsaken heretofore, because of the negligence 

 of writers. A positively tedious comparison of leaves, without 

 the remaining points having been carefully investigated and 

 clearly set forth, renders the amateurs fully as confused as are 

 the botanists themselves. Moreover, the fruits especially must 

 be observed, and these only in their mature state." 



In Handel-Mazzetti's work there was given an admirable 

 presentation of the various species of the genus. Even this 

 valuable monograph, however, was rather inadequate for a critical 

 opinion of the North American species, since there were a number 

 of the more recently proposed species of which he obviously had 

 not seen authentic specimens. In certain other cases his exami- 

 nation of American specimens was too limited, and I fail to find 

 even the slightest mention of some of the species proposed by 

 American authors previous to 1907. What seems worst of all, 

 however, is that the many valid results of his research have been 

 passed by almost unnoticed until the present day in this country. 

 Taxonomic literature relating to Taraxacum in America is still 

 weighted with inaccuracies that ought to be corrected. 



The study presented herewith was undertaken in 191 8. From 

 the beginning the main purpose has been to correlate much of the 

 material in American herbaria with Handel-Mazzetti's treat- 

 ment, to corroborate his results where possible, to correct or 

 improve and to augment where there was need, and then to present 



* For reference to the works of Fries, Km 11, and Voith, touching this point, 

 see DC. Prodr. 7:145 (footnote). 1838. 



