470 



The operculum is a useful character in the discrimination of species, but 

 variable, like everything else in Eucalyptus. 



Mr. R. H. Anderson has assisted me in the following grouping from the 

 drawings, but it must be borne in mind that shrinkage sometimes alters the shape 

 of the operculum. It will be seen that the majority of species fall into Groups 3 and 5. 



1. Hemispherical. This and the next group run into each other. 



2. Hemispherical in outline, but with a mucro or umbo. 



3. Hemispherical-conical. These are intermediate between the hemispherical 



and conical. Some under this heading tend to fall within Group 2. 



4. Egg-shaped. These are obtusely and symmetrically conical, like the end of 



an egg. 



5. Conical. Usually acute. Merges into 3. 



0. Tapering or elongated. In this group there are readily distinguishable two 

 sub-groups : — ■ 



(a) Tapering symmetrically. 



(b) Broad at base, but narrowing quickly into a narrow beak. 



7. Oblong, rounded at apex. 



8. Pileiform or dilated. 



9. Special forms. Buds reminiscent of cloves in shape. 



1. Hemispherical. 



E. amygdalina (flattened). E. Kybeanensis (or 3). 



E. aspera (or 3). E. nitida (flattened). 



E. capitellata (or 3). E. obiusiflora (sometimes pointed). 



E. clavigera. E. papuana (or 3). 



E. coriacea (or 3) (sometimes flattened). E. Risdoni. 



E. gigantea (or 4). E. Sieberiana (or slightly urn- 



bonate). 



E. alba. E. Griffithsii. 



E. angulosa. E. Guilfoylei. 



E. Campaspe. E. Houseana. 



E. collina. E. odorata var. calcicultrix. 



E. comigata. E. Preissiana. 



E. gamophylla. E. salmonophloia. 



E. gracilis. 



E. tessellaris (or with a mucro). 



