GK0UPING OF SPECIES. 85 



agreeing* in one characteristic, differ considerably among- themselves 

 in other respects, especially in the shape of the leaves. None of these 

 species have permanently opposite or stemless leaves. 



Leaves of seedlings hairy: Eucalyptus calophylla, E. citriodora, E. 

 corniced, E. eugenioides, E. macrorhyncha, and E. paniculata. 



Leaves permanently horizontal, darker above than below: Eucalyp- 

 ti/* botryoides, E. calophylla, E. corymbosa, E. diversicolor, E. resini- 

 fera, E. robusta, and E. sallgna. The foregoing species being all indig- 

 enous to the moister regions of Australia, the characteristic placing 

 of the leaves vertically is not necessaiy. A few species, including 

 E. corynocalyx, E. diversicolor , E. pilularis, and E. punctata, while 

 not having their leaves so distinctly permanently horizontal, have 

 leaves with the two surfaces more or unless unlike. 



FLOWERS AND SEED CASES. 



Flowers commonly in threes: Eucalyptus leucoacyl on , E. longifolia, 



E. villlilHl/ix. 



Flower clusters borne on a distinctly flattened stalk: Eucalyptus 

 botryoides, E. goinphocephala, E. goniocalyx, E.occiil -n talis, E. punc- 

 tata, E. resinifera, and E. saligna. 



Flower-bud covering long and prominent: Eucalyptus cornuta, E. 

 marginata, E. occidentalism E. siderophloia, and E. tereticornis. 



Seed cases large (one-half inch to 1\ inches in diameter): Eucalypti/* 

 calophylla, E. corymbosa, E. globulus, E. gomphocephala, E. longifolia, 

 E. marginata, and E. robusta. 



Seed cases very small (one-tenth to one-sixth inch in diameter): 

 Eucalyptus crebra, E. microtheca, E. poty< mth em.a \ and E. populifoUa. 



ClilMATIC ADAPTATION. 



In the following paragraphs an attempt is made to list species espe- 

 cially adapted to various climatic situations. It is not claimed that all 

 that may be grown successfully in any one region are listed, hut it is 

 thought that the more promising ones are included. 



Adapted to hot, humid regions: Eucalyptus botryoid\ 8, /'.'. calophylla, 

 /:'. citriodora, E. cornuta, E. marginata, and E resinifera. Of the 

 above, E. botry aides, E. citriodora, and E. resinifera arc the most 

 likely to thrive in America and to produce useful timber. 



Adapted to warm, moderately humid regions having light winter 

 frosts: Eucalyptus amygdaUna, E. botryoides, E. cornuta, E. corym- 

 hosu, K. corynocalyx, E. cn-hra. E. divert/color. /:'. globulus, E gompho- 

 cephala. E. goniocalyx, /:'. ocddentalis, E.robusta, E rostrata, E. rudis, 

 E. sideroxylon, E tereticornis, and /:'. viminalis. Of the foregoing, E. 

 botryoides, E. diversicolor, E. globulus, E gomphocephala, and /;'. tereti- 

 cornis seem best adapted to American climatic conditions, and most 

 suitable for producing timber valuable for commercial purposes. 



