12 



1 6 The Trees of Great Britain and Ireland 



of those in the Himalayas and eastern Asia. Many of these are in cultivation, 

 and may be grouped into the following subsections :— 



(a) Erythrobalanus, Spach. 



Fruit ripening in two years ; aborted ovules in the upper part of the 

 acorn ; cupule scales all appressed. Trees with bristle-pointed leaves, confined 

 to North America, and comprising the oaks there known as willow, black, and 

 red oaks. The introduced species are— g. Phellos, Q. cinerea, Q. imbricaria, 

 Q. nigra, Q. marylandica, Q. cuneata, Q. ilicifolia, Q. velutina, Q. Kelloggii, 

 Q. rubra, Q. coccinea, Q. palustris, Q. Schneckii, with deciduous foliage; and 

 Q. agrifolia} Q. Wislizeni, and Q. crassipes, with evergreen foliage. 



(b) Cerris, Spach. 



Fruit ripening in two years ; aborted ovules at the base of the acorn ; cupule 

 scales spreading, often reflexed. 



Trees of Europe, northern Africa, and Asia. The species in cultivation 

 are — Q. Cerris, Q. jEgilops, Q. castaneafolia, Q. Libani, Q. macedonica, Q. 

 serrata, Q. variabilis, and Q. dentata^ with deciduous foliage ; Q. alnifolia and 

 Q. coccifera, with evergreen foliage. 



(c) Leucobalanus, Engelmann. 



Fruit usually ripening in one year ; aborted ovules at the base of the acorn ; 

 cupule scales appressed. 



Trees of North America, Europe, northern Africa, and Asia. All the oaks 

 which are known to produce timber of the first quality belong to this sub- 

 section, which may be divided into three groups : — 



(a) Leaves evergreen. The species in cultivation are — Q. Ilex and Q. Suber^ 

 of the Mediterranean region, Q. incana^ and Q. semecarpifolia^ from the Hima- 

 layas, Q. phillyrceoides^ from Japan, and Q. chrysolepis and Q. glabrescens from 

 North America. 



(^) Leaves deciduous. The white oaks of North America. The species 

 in cultivation are— g. alba, Q. lyrata, Q. macrocarpa, Q. lobata, Q. bicolor, Q. 

 Prinus, Q. Muehlenbergii, Q. prinoides, and Q. obtusata. 



(7) Leaves deciduous. Natives of the old world. The species in cultiva- 

 tion are— ^. pedunculata, Q. sessiliflora, Q. lanuginosa, Q. Toza, Q. conferta, 

 Q. Mirbeckii, Q. pontica, Q. macranthera, Q. lusitanica, Q. infectoria, Q. glandu- 

 lifera, Q. grosseserrata. 



II. Cyclobalanopsis. 



Flowers as in Lepidobalanus. Cupule of the fruit cup-shaped, with scales 

 united into concentric zones. 



Evergreen trees, inhabiting the Himalayas, China, and Japan; leaves 



3 tS ?eltT to' ''' '"" '"/"' ^'"- ' 1° '^'^ ^P«"- '^- fr"it riP^'^ in one year. 



O sJec^J^2\t?'-7"^'""'^"^ C "' ^"^^^^■^g^""- I" Q- Suier, var. occidentalu, Q. phillyraoides, Q. incana, and 

 y. semecarpifolta, the fruit npens in the second year. ^ r j 1 vi 



