PREFACE. Vil 
ticular organs, common to the greater part of plants; and 
collecting together, in classes and subdivisions, the several 
plants which agreed in respect to the structure or number 
of these chosen organs, without any regard to the affinity a 
more accurate observation of the whole structure of the 
plant might develope. Of these mere artificial methods, 
as they are termed, Rivinus, professor at Leipzig, was the 
introducer, and he took his primary divisions from the 
regularity or irregularity of the corolla, or what is com- 
monly called the bloom, and the number of parts into 
which it is cut, and subdivided each of these primary 
divisions in a uniform manner, according to the nature of 
the fruit. In this system he was followed by Hebenstreit, 
Knaut, Ludwig, and Ruppius. The botanists of this school 
considered the method of Rivinus in its proper light, as 
being merely a ready means of determining the family, or 
what is now called the genus, to which any plant belongs; 
and, therefore, contented themselves with following it up 
to that point, leaving the further knowledge of plants to be 
sought for in the authors who have arranged their works 
by the natural affinities of plants, or other considerations. 
The want of the power of locomotion, by which plants 
are most evidently distinguished from the generality of 
animals, and the consequent inability of approaching 
each other, if the organs of reproduction were seated in 
distinct individuals and the analogy of animal generation 
strictly observed, while, at the same time, they are, from 
the same immobility, liable to a variety of accidents, which 
animals elude by the. power of changing their place, 
rendered neGessary the adoption of peculiar contrivances 
to preserve and multiply the species in which some analogy 
may be observed with those of animals, more apparent 
however than real. 
The prurient mind of Linnzeus, so visibly exhibited in 
his mode of describing bivalve shells, was struck by the 
sreat difference between animals and vegetables in this 
respect; and he immediately applied himself to arrange 
