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University of California Puhlications in Botany [Vol. 6 



seemed aberrant in any previously accepted genus. Professor Nelson 's 

 treatment possesses merit in that it emphasizes the close affinity between 

 the members of this group, to which H. eximius is now added. But, 

 this relationship may also be expressed by the use of a subgeneric name 

 under Haplopappus, and this method is to be preferred, since no mor- 

 phological characters of the flower which would serve to separate 

 Tonestus have as yet been pointed out. Furthermore, it is very undesir- 

 able to increase further the number of Haplopappus segregates until 

 some investigator has had opportunity to make an exhaustive study of 

 all of the forms, including those of South America, the home of the 

 original species. 



Style-branches of disk-flowers in Haplopappus and Macronema. — Fig. 1. 

 Haplopappus (Tonestus) Lyallii Gray, from Cusick's no. 2093, Oregon. Fig. 2. 

 Haplopappus {Tonestus) eximius Hall, from type material. Fig. 3. Macronema 

 ahcrrans Nelson, from type collection (Herb. Gray). Fig. 4. Macronema 

 suffruticosa, from Congdon 's Mariposa County, California, specimens. — All the 

 figures are enlarged about seventeen diameters. 



Whatever the ultimate fate of Tonestus may be, it seems certain 

 that it is more closely related to true Haplopappus and to Stenotus 

 than to Macronema. A technical character of considerable importance 

 for the separation of Tonestus from Macronema was apparently over- 

 looked by Nelson, although since used by Rydberg in his Flora of 

 Colorado, namely the shape and relative lengths of the appendage and 

 stigmatic portion of the style-branches. In the former the appendage 

 is somewhat obtuse and shorter than or only etjualling the stigmatic 



