SUMMARY OF RESULTS FROM THIS RESEARCH. 



Callitris. 



I. A re-classification of the genus Callitris and its separation from Wiildrliig- 

 tonia and Tetraclinis, which genera we find arc restricted to South and 

 North Africa, respectively. 



2 A new sequence of the species of Callitris founded upon the broad grounds 

 of botanv, chemistry, and other cognate sciences — a system even more 

 enlarged than that laid down in our previous work, " Eucalypts and their 

 Essential Oils," is advanced. 



3. The restoration of almost all Robert Brown's and Allan Cunningham's species 



of Callitris to specific rank. 



4. The Callitris pines have been found to retain an intimate connection, both 



in botanical and chemical characters, throughout their geographical 

 distribution. 



5. A remarkable constancy of morphological characters was found to be 



preser\-ed amongst the species of Callitris. 



6. There is a singular absence of varietal forms amongst the Callitris. 



7. Phylloclades are not found in Callitris. 



8. The cause of the decurrence in the leaves of the Callitris, and the effect of 



climatic conditions in the disposition of the stomata of Callitris species, 

 are suggested. 



g. It is shown that a similar arrangement of the stomata obtains in Callitris as 

 existed in the leaves of Lepidodendron Hickii, of the Carboniferous period. 



10. That similar papillose projections surrounding the stomata in certain species 



of Callitris occur also in the genus Sciadopitys, of Japan. 



11. The anatomy of the leaves of the Callitris is fully detailed. 



12. A general conformity holds in the structure of the leaxes of Callitris species, 



only minor differences in specific characters, being recorded. 



13. Features distinctive from those of other Coniferae occur in Callitris leaves. 



14. The presence of a manganese compound, probably the "resin" of previous 



workers, in some of the timber cells of the Australian Coniferae, as well 

 as in the leaves and bark of Callitris, is recorded. I liis substance is found 

 to occur also in the lamella of the Callitris. 



