Axelrod: The Pliocene Verdi Flora of Western Nevada 129 



from Manchuria and Japan southward into the high mountains of Yunnan, are 

 regularly the small size of the fossil, and thus seem to more nearly represent its 

 closest modern counterpart. The leaves of P. tremula and P. grandidentata both 

 closely resemble those of P. washoensis, which is probably ancestral to P. sub- 

 washoensis. 



Since the poplar and aspen leaves described from the Mulholland and Deschutes 

 flora are similar to the Verdi material, and to leaves of the living P. tremula 

 davidiana, they are herewith transferred to P. subwashoensis. 



Occurrence. — Verdi, Nev.: U.C. Mus. Pal. (loc. P102), hypotypes nos. 2005- 

 2008 ; homeotypes nos. 2009, 2010. 



Salix boisiensis H. V. Smith 

 (PL 22, figs. 10-12) 



Salix boisiensis H. V. Smith, Amer. Mid. Nat., vol. 25, p. 498, pi. 2, fig. 3 ; pi. 4, fig. 8, 1941 ; 

 Axelrod, Carnegie Inst. Wash. Pub. 553, p. 194, pi. 36, figs. 8-10, 1944. 



Two obovate leaf impressions in the Verdi collection are similar to the specimens 

 of Salix boisiensis in the Thorn Creek and Sonoma floras. Like them, the Verdi 

 leaves show relationship to those produced by the living S. scouleriana Barratt 

 (=S. nuttallii Sargent). This is a common willow in the Sierra Nevada, ranging 

 northward to Alaska and eastward through the Rocky Mountains. 



Occurrence. — Verdi, Nev.: U.C. Mus. Pal. (loc. P102), hypotypes nos. 2011, 

 2012. 



Salix truckeana Chaney 

 (Pi. 22, figs. 9-11; pi. 23, figs. 1-3) 



Salix truclceama Chaney, Carnegie Inst. Wash. Pub. 553, p. 316, pi. 52, figs. 2-6, 1944; Axelrod, 

 Univ. Calif. Pub. Geol. Sci., vol. 33, p. 286, pi. 26, figs. 2, 1956. 



The leaf impressions of this black willow are well represented in the Verdi flora. 

 Among living species, close relationship is apparent with leaves of Salix gooddingii 

 Ball of central and southern California and the southwestern United States. All 

 these areas have milder winters than those now found in western Nevada. 



Occurrence.— Verdi, Nev.: U.C. Mus. Pal. (loc. P102), cotypes nos. 1991-1993; 

 hypotypes nos. 1995-1997 ; homeotype no. 1994. 



Family FAGACEAE 



Quercus prelobata Condit 

 (PL 23, fig. 10) 

 Quercus prelobata Condit, Carnegie Inst. Wash. Pub. 553, p. 43, pi. 7, figs. 3, 4, 1944. 



A fragmentary impression of a white oak leaf in the Verdi collection at the 

 U.S. National Museum is well within the range of variation of the Remington Hill 

 Q. prelobata Condit. Like that material, the Verdi specimen resembles leaves of the 

 common California white oak, Q. lobata Nee. Q. utahensis (DeCandolle) Rydberg 

 of the southern Rocky Mountain region also has similar leaves. 



Occurrence. — Verdi, Nev.: U.S. National Museum. 



