PRELIMINARY REMARKS. 5 
Following the views before suggested, 1 proceed to offer, in the first place, the pro- 
posed classification of the entire family, based on the principles already explained. To 
this arrangement will be prefixed, in each tribe, a review of most of the South- 
American genera thus eliminated, noting the peculiar characters by which they are 
distinguished, and followed in each case by a careful enumeration of the several species 
and their synonyms: we thus dispose of the great mass of recorded species of hitherto 
doubtful or wrongly assigned position. Whenever I have had access to the specimen 
described, and have been able to analyze a flower, a complete enumeration of all its 
characters is given in regular and continuous sequence. These may seem to many unne- 
cessarily long ; but, in my estimation, no diagnosis can be too long when it is confined to a 
simple narrative of facts : it is by such a method alone that we can with confidence assign 
any plant to a particular group, and distinguish it from other cognate species. But in those 
instances where the plant described by others has not been seen, its diagnosis has been 
remodelled, by arranging its given features in the same order of sequence as in the former 
case, thus avoiding the disruptions usually effected by authors—such breaks making it 
more difficult to compare one species with another, and to decide upon their identity or 
difference. , 
In order to render the details of the genera more intelligible, and the differences 
between the several groups more apparent, 1 propose to illustrate by analytical drawings 
the leading characters of their floral or carpological structure. 
