IV. GRADES OF SPECIES. 37 
described species which have been subsequently found (or supposed) 
to be correctly divisible into other subordinate species. The Ver- 
species are those which remain undivided, and seemingly are 
indivisible. The Sub-species are those into which the super- 
species have been or may be divided. Of course, the same terms 
may be used in the reverse process, that of uniting or re-uniting 
species. Various botanists still regard the ‘ super’ to be the true 
species, and only co-equal with the ‘ver-species ;’ while others 
look on the * sub’ as co-equal with the ‘ ver-species.’ 
Three other terms have also been employed; namely, “ Aggre- 
gate, Integrate, Segregate species ;” which certainly better express 
the facts, apart from all theory about the reality of species. And 
just because of their superiority in sense and logic they will be 
longer in coming into use than the terms Super-species and Sub- 
species. They might be defined in the same words as the other 
three terms; but they better admit of practical application without 
involving any inconsistency real or seeming. The Aggregate 
species is the compound which has been, or may be, divided into 
quasi-specific parts. The Segregate species are those quasi-specific 
parts themselves. The Integrate species stands between them, as 
an undivided or indivisible whole. The chief advantage of these 
terms is, that they admit of any change or variation in use, to suit 
the actual views of botanists, however diverse and changeable 
those views may be. The very same species may be placed as an 
aggregate by one botanist, as a segregate by another botanist, 
without contradiction between them; because the words simply 
express the fact of union or severance, without necessarily raising 
the controversial question, as to which among them are equal to 
Ver-species. For instance, in the English Flora by Smith the 
Linnean Ranunculus aquatilis is an aggregate species (there 
treated as a specific integrate) including four principal forms or 
varieties, which are now usually accepted for true species ; namely, 
heterophyllus, pantothria, circinatus, and fluitans. Regarded as 
subdivisions of Ranunculus aquatilis, these latter may be denomi- 
nated four segregate species ; although Smith himself, like many 
other botanists, hit upon a false line of separation between 
