632 SPECIES OF EUCALTPTS EIEST KNOWN IN EUROPE, 



living state, Tvoiild sujDpose that they were allied, the hark and 

 wood heing so very different. Though bearing a great resemblance 

 to E. siderojyJiJoia, it differs from that species in the shape and 

 length of the operculum, as well as in the smaller size of the 

 leaves. 



In concluding this paj)er, it may be remarked that a review of 

 the species first known in Europe is interesting, not only in an 

 archaeological point of view, but as affording an illustration of 

 the progress which has been made in descriptive Botany within 

 the last centur}^ When the short and unsatisfactory descriptions 

 of Smith's are compared with tliose of Mr. Bentham and Baron 

 Mueller, one cannot help seeing the advance which has been 

 made in the delineation of species, and the satisfactory steps 

 which have been taken in seizing upon those features which 

 connect them together. Botanists have always felt a difficulty 

 in dealing with the genus Eucalyptus, because, whilst many of the 

 species have flowers and fruits very similar, they are nevertheless 

 perfectly distinct in wood, bark, and habit. It was not until 

 Baron Mueller described many of them in the second volume of 

 the Fracjmenta, and subsequently in connection with Mr. Bentham 

 in the third volume of the Flora Austral iensis, that a subject 

 which had remained dormant for nearly half a century was again 

 forced upon the scientific world. "Whilst, however, much was 

 done by these works in the determination of species, it remained 

 for Baron Mueller to follow up the subject in \i\^Eucahj'ptogra'pliia. 

 He has already described and figured SO sj^ecies of the genus^ 

 and these are so well defined, that in studying the descriptions, 

 it is impossible to apply them to any other trees than those 

 ntended bv the author. 



