North American Polygonaceae. 44 



Eriogonum stellatum and later to E. tripodum. Professor Greene 

 has lately said* that it cannot be associated with E. stellatum, and 

 to prevent the excellent E. tripodum from becoming a composite 

 species we must describe it as new. Besides the less strict habit 

 and the broader leaves, the glabrous calices serve as a ready means 

 of separation between this species and E. tripodum. 



The original specimens were gathered by Professor Greene on 

 the southern and western slopes near the summit of Mount Ham- 

 ilton, California. 



Eriogonum pulvinatum. 



Perennial, matted, densely woolly-tomentose. Stems much 

 branched, woody below: leaves crowded, spatulate, 5-8 mm. long, 

 obtuse, wooly ; blades thick, slightly revolute, narrowed into winged 

 petioles: scapes erect, 1 — 1.5 cm. long, topped by a head of several 

 involucres: involucres turbinate-companulate, 3-4 mm. high, 

 partially deciduous; segments 5 triangular, green, shorter than 

 the hyaline tube : calices oblong-campanulate, 2.5-3 mm. long, 

 villous within and without, the hairs often pointing downward ; 

 segments oblong, obtuse, erect, twice as long as the tube, the 

 inner 3 narrower than the outer : filaments slender, exserted, vil- 

 lous at the base : style-branches elongated : achenes 2 mm. long, 

 3-angled, densely villous with tangled hairs. 



In dry soil, southern Utah. Spring and summer. 



A dwarf species belonging to a group peculiar to the higher 

 altitudes of the Sierra Nevada Mountains. It is related on the one 

 hand to Eriogonum gracilipes and on the other to E. nivale. The 

 glandless peduncle is sufficient to separate it from the former 

 species. From E. nivale it differs in the looser tomentum, the 

 clustered involucres and the villous calyx-segments. 



The original specimens were collected by Mr. M. E. Jones, at 

 Milford, Utah, June 17, 1880. Altitude about 1,500 meters. 



Eriogonum Siskiyouensis. 



Perennial from a shrubby base, nearly glabrous. Stems very 

 short or sometimes several cm. long : leaves crowded at the ends 

 of the branches, 5-10 mm. long ; blades elliptic or oval, acute or 

 acutish, glabrous above, slightly tomentose beneath, somewhat 

 revolute, short-petioled : scapes erect, simple 3-8 cm. tall, fur- 

 nished with a whorl of bracts above the middle: involucres cam- 



* Pittonia, 3:201. 



