259 



The additional species in North Greenland are one species of 

 Erigeron, two of Gnaphalium, and one of Artemisia. 



All four members of the chicory family belong to the genus 

 Taraxacum of which the dandelion is a member. Of these one 

 has not been found outside of Ellesmere Land and North Green- 

 land, two more are found only there and in arctic America, while 

 the fourth (not found in Ellesmere Land, nor America) is common 

 to Greenland, arctic Europe, and Asia. All four of the arctic 

 dandelions are now represented in the herbarium of the New York 

 Botanical Garden. A few years ago we had only one. Two 

 more were collected by Dr. Wolf and the last one by Dr. Goodsell. 

 New York Botanical Garden 



(To be continued) 



NEW COMBINATIONS FROM THE GENUS 

 EUPHORBIA 



By J. C. Arthur 



The rusts inhabiting the several species of the genus Euphorbia, 

 as ordinarily understood, have been variously treated by my- 

 cologists. In the recent monograph of the genus Uromyces by 

 Sydow, the North American forms having aecia, uredinia and 

 telia are segregated under four species, following the authority 

 of Tranzschel, who in turn based his studies largely upon the 

 published results of cultures made by the writer. In the treat- 

 ment of this group of rusts in a forthcoming number of the 

 North American Flora, the writer proposes to consider the four 

 species recognized by Sydow as representing "physiological 

 species," or races, belonging to a single species of rust. As 

 these races conform fairly well to the genera into which the 

 genus Euphorbia has been segregated, the writer further proposes 

 to use the names of the segregates, rather than list all the hosts, 

 about thirty-five, under the genus Euphorbia. A few" of these 

 species have not yet been transferred to the segregated genera, 

 and rather than make the transfer of phanerogamic names in a 

 work devoted to fungi, the present method is taken to place the 



