STANDLEY TREES AND SHRUBS OF MEXICO. 189 



2 em. wide, 3 to 6 cm. long), thick and hard, from minutely scurfy glabrescent, 

 elliptic or oblong to ovate, mucronately acute, truncate at base or subcordate, 

 short-petioled, characteristically repandly few-toothed ; acorn narrowly ellip- 

 soid. S mm. in diameter, 15 to 20 mm. long, one-third included, the rounded cup 

 with blunt appressed scales ; wood rather soft, strong but brittle, close-grained, 

 dark brown, its specific gravity about 0.93. 

 The acorus are said to be of good quality as food. 



59. Quercus durifolia Seemen, Bot. Jahrb. Engler 29: 95. 1900. 

 Durango ; type locality, Durango. 



Twigs slender, subglabrescent ; buds glossy light brown, small; leaves (decidu- 

 ous?) very small (1 cm. wide, 3 to 4 cm. long), firm, canescent beneath, short- 

 lanceolate, mucronately acute, obliquely subtruncate at base, short-petioled, 

 mostly with a few short teeth ; acorn round-ovoid, under 10 mm. in diameter, 

 fully half included, tlie rounded cup with blunt appressed scales. 



60. Quercus eduardi Trel. 



Quercus oligodonta Seemen, Bot. Jahrb. Engler 29: 96. 1900. Not Q. oligo- 

 donta Saporta, 1879. 



Durango, Jalisco, and Tepic; type from Durango. 



Small deciduous tree with slender glabrescent twigs and glossy, light brown, 

 small buds; leaves small (2 to 4 cm. wide, 3 to 6 cm. long), firm, rather per- 

 sistently stellate-scurfy beneath, oblong-elliptic, mucronately subacute, .slightly 

 cordate, with short glabrescent petiole, entire or with several aristate teeth ; 

 acorn ovoid or oblong, scarcely 8 mm. in diameter and 10 mm. long, half in- 

 cluded, the turbinate cup with rounded appressed scales. 



" Encina colorada " ; the dark red wood valuable. 



61. Quercus devia Goldman, Contr. U. S. Nat. Herb. 16: 322. 1916. 



Baja California ; type locality, between El Sauz and Chuparosa. 



Moderately large evergreen tree, about 20 meters high, with slender glab- 

 rescent twigs and small, acutely ovoid, glabrescent buds ; leaves rather small 

 (1 to 3 cm. wide, 5 to 10 cm. long), often somewhat dingy-tomento.se beneath, 

 broadly lanceolate or oblong, very acute, subcordate, rather short-petioled, 

 aristately toothed ; acorn oblong, 8 mm. in diameter, 15 to 20 mm. long, the 

 shallow cup with blunt appressed scales. " Encina negra." 



62. Quercus hypoleuca Engelm. Trans. Acad. Sci. St. Louis 3: 384. 1877. 

 Chihuahua and Sonora. New Mexico (type locality, Santa Rita) and Arizona. 

 Shrub or small to moderately large subevergreen tree with rather slender 



gray-tomentose twigs and small red buds with ciliate scales ; leaves rather small 

 (2 to 3 cm. wide, 5 to 10 cm. long), rugose, revolute, blue-green above, densely 

 pale-tomentulose beneath, lanceolate, aristately very acute, rounded at base, 

 moderately petioled, typically entire ; acorn narrowly conic-oblong, 8 mm. in 

 diameter, 10 to 15 mm. long, scarcely one-third included, the turbinate cup with 

 blunt, appressed, at first very tomentose scales ; wood hard and strong, close- 

 grained, dark brown, the specific gravity about 0.80. 



63. Quercus scytophylla Liebm. Overs. Dansk. Vid. Selsk. Forh. 1854: 180. 

 1854. 



Oaxaca and Michoacan ; type locality, Yalala to Yabochi, Oaxaca. 



Twigs rather slender, glabrescent; buds small, glossy brown, glabrescent; 

 leaves (deciduous?) large (7 to 8 cm. wide, 13 to 15 cm. long), rugose, densely 

 creamy-tomentulose beneath, typically obovate and acute, obliquely acute or 

 rounded at base, moderately petioled, characteristically with several short 

 aristate teeth above ; acorn ovoid, 10 mm. in diameter, 15 to 20 mm. long, the 

 rounded or saucer-shaped cup with blunt appressed scales. "Encina" (Micho- 

 acan). 



