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by the position and priority of vegetable groups as revealed by geolo- 

 gical research. Thns it brings into some sort of progressive connexion 

 Eucoids, Equisetaceae, Coniferae, and Palmaceae. Even in members of 

 the same family corroboration is received from previously recognised 

 peculiarities. Thus in the Ash order we have the Ash having apetalous 

 flowers, and the Privet having flowers with petals. The inflorescence 

 in the first case is a raceme, in the second it is the more developed 

 panicle. This, however, is a portion of the subject to which I have not 

 had time to give sufficient attention ; and the developments of parts 

 may not always be coequal. 



Considered from a geological point of view this arrangement of 

 affinities fairly coincides with scientific discoveries. Eor, in the Lower 

 and Middle Palaeozoic epochs, Eucoids, Equisetaceae, and Gymnosperms 

 are first found ; whilst in the Upper Palaeozoic some doubtful Monocotyle- 

 dons begin to present themselves. When, afterwards, the Dicotyledons 

 make their appearance, the Amentaceae are amongst the earliest to 

 show themselves. In conclusion, I wish to remark that, where the 

 word " type" or " antetype" has been used, I have not meant to indi- 

 cate a fixed form, but merely a remarkable stage, which may be a rest- 

 ing point in transitional development. 



