32 TRELEASE— UNUSUAL BLACK OAKS. 



flowering instead of deferring fertilization and maturation of fruit 

 for a year. 



The first of these species was collected by Dr. J. N. Rose of the 

 United States National Herbarium in the mountains of Tepic in 

 1897; the second, by Monsieur E. Langlasse in the Sierra of Alicho- 

 acan or Guerrero in 1899; and the third, by Professor C. Conzatti 

 of Oaxaca in the southern Cordillera in 1907. They constitute a 

 natural group which in some respects suggests relationship with that 

 embracing Q. crassifoUa, 0. fiilva and Q. stipitlaris, which likewise 

 mature their fruit in the first season though differing greatly in 

 some other respects. The common and differential characters of 

 these new species may be stated thus : 



Raceniiflorae. — Moderateh^ large trees with stout tomentose twigs, 

 rounded buds, large cordate pandurate-obovate or orbicular concave aristately 

 dentate petioled leaves impressed-veiny above and tomentose beneath, and 

 small annual fruit in elongated raceme- or spike-like catkins, the thin cupules 

 with tomentose scales. — Western Sierra Madre and southern Cordillera of 

 Mexico. 

 Petioles long (20-30 mm.). 



Leaves longer than broad, somewhat repand Q. Urbani. 



Leaves isodiametric. aristate from the nerves Q. radiata 



Petioles short (scarcely 15 mm.): leaves isodiametric Q. Conzattii. 



Quercus (Erythrobalanns) Urbani n. sp. 



A tree 8-10 m. high, with tortuous trunk. Twigs stout, with 

 dense yellowish tomentum persisting through the second season. 

 Buds rounded, somewhat tomentose. Leaves large (15x16 cm.), 

 deciduous, pandurate-subobovate, shortly acuminate, cordate-auricu- 

 late, lightly hollowed between the aristate ends of the veins, con- 

 vex, glossy and glabrous except for the impressed veins above, 

 densely creamy-tomcntose beneath; petiole yellow-tomentose, 3x25 

 mm. Flowers unknown. Fruit annual, small, in yellow-tomentose 

 spikes 80-110 mm. long, densely flowered toward the end; cup small 

 (10 mm.), hemispherical, with thin appressed blunt fulvous-tomen- 

 tose scales ; acorn ovoid, 10 mm. long, canescent. 



Called encino cucharilla, from its deeply spoon-shaped leaves. 



Western Sierra Madre of ]\Iexico. at 1,800 m. {Langlasse. 1066, 

 June 20, 1899), from Michoacan or Guerrero, — the type in the her- 

 barium at Dahlem, for the privilege of studying which I am indebted 

 to Professor Ignaz Urban, of that institution. 



