IN EXTKA-TROPICAL COTJNTUIES. 269 



and Soutt-West Asia. So called from the red dye furnished 

 by the Coccus ilicis from this Oak. It also supplies tanners' 

 bark containing about 8 per cent, tannin (Muspratt) . The 

 huge and ancient Abraham's Oak belongs to this species. The 

 tree likes rich woods. 



Quercus cocciuea, Wangenheim. 



The Black Oak of North America. Height 100 feet; stem 

 diameter 5 feet. Foliage deciduous. The yellow dye known 

 as quercitron comes from this tree. It is much more power- 

 ful than that of Woad (Bancroft) . With alumina the tinge 

 of the bark is bright yellow, with oxyde of tin it is orange, 

 withoxyde of iron it is drab (Porcher). Q. tinctoria (Bartram) 

 is a variety. The bark of the variety called Scarlet Oak is 

 practically far inferior in value to that of the Black Oak 

 (Meehan) . Bark rich in tannic acid, about 8 per cent. (Gard. 

 Chron.). Dr. Engelmann found the Black Oaks twice as fast 

 in growth as the White Oaks of the United States. The 

 Bartram's Oak (Q. heterophylla) is according to him a hybrid 

 between the Willow Oak and Scarlet Oak. Hybrid Oaks 

 produce acorns fit to germinate. 



Quercus cornea, Loureiro. 



China. An evergreen tree, 40 feet high. Acorns used for food. 



Quercus cuspidata, Thunberg.* 



Japan. The acorns, when boiled or roasted, are edible and 

 regularly sold in Japan for food (Rein) . A magnificent Oak, 

 grand in its proportion, bears acorns in bunches or strings, of 

 very sweet taste when baked like chestnuts, but only of the 

 size of kidney beans (F. C. Christy) . 



Quercus densiflora, Hooker and Arnott. 



CaHfornian Chestnut Oak. A large evergreen tree of beautiful 

 outline, dense foliage and compact growth. Bark very valu- 

 able for tanning ; wood, however, subject to rapid decay (Prof. 

 Bolander) . Quercus Douglasii is another tall Oak of Cali- 

 fornia. 



Quercus dentata, Thunberg.* 



Japan. This is one of the species on which the Oak Silkworm 

 (the Yama Mayon) lives. 



Quercus dilatata, Lindley. 



From the Himalayas to Afghanistan, at elevations from 4,500 



