1tS6 Sir Edward Ffrcnch Bromhead on the Arrangement of 



natural scheme remains to be collected by induction, from a 

 comparison of the arrangement of species in genera, genera in 

 families, and families in groups, alliances, and races. 



The Parallelisms and Correspondences closely examined may 

 hereafter lead to making the limitation of the groups mutually 

 more definite, and may suggest points of structure. 



The Table is to be considered as a sketch for future correc- 

 tion, in which certain families and groups may change places, 

 though the whole may present something like a fixed basis to 

 work upon, and definite tangible limits of inquiry. 



There is a general tendency in the groups to form themselves 

 into a re-entering or fusiform series : the same tendency is shewn 

 in sets of groups, and in sets among each other. This causes 

 the greatest difficulty in arrangement, as families, prima Jade 

 adjoining, may form the terminating points of the group ; and 

 when two corresponding groups lie near, the combined effect of 

 relation and affinity is most embarrassing. If the reader is sur- 

 prised at finding any two families in separate groups, let him 

 apply the groups to each other ; and a correspondence will pro- 

 bably appear on comparing the preceding and succeeding groups 

 of each series progressively and regressively. 



Botanists ought, I think, to lean to the division of families, as 

 facilitating their relative arrangement ; the formation of groups 

 will, in many cases, be a useful check to improper compression 

 "or division. When orders have been divided, much error has 

 arisen from authors continuing to declare an affinity to the or- 

 der under its old name, though that affinity may be confined 

 exclusively to the separated order. 



The mode of investigation here followed has, of course, often 

 failed, the evidence for different situations being equally ba- 

 lanced. This has been the case among single families, and in 

 the parallel of the Amentaceous families, and also among the 

 Endogenous families, where authors writing at random have given 

 full scope to artificial arrangement, and compared each family 

 with almost every other. So also from circulation, parallelism, 

 and correspondence, it has been impossible, without something 

 arbitrary, to separate some others. 



