XXX INTRODUCTION. 
main features of the distribution of existing animals, not those of any or all past 
geological epochs. Should we ever obtain sufficient information as to the geography 
and biology of the earth in past epochs, we might indeed determine approximately what 
were the Pliocene, Miocene, or Eocene zoological regions; but any attempt to exhibit 
all these in combination with those of our own period must lead to confusion.” This 
objection applies with equal force to any botanical division; and as a critical exami- 
nation of Engler’s scheme would involve the discussion of questions beyond the scope 
of the present inquiry, it is sufficient for the purpose to have brought it under notice, 
though it should be added that it is full of valuable matter, and has been largely 
utilized in the present work. | 
The other scheme referred to above is by Dr. Drude. It was originally published 
in 1884 *, and again in 1887 as an independent work}. As explained in the title 
given below, this is a representation of the present conditions of the distribution of 
plants; hence it has a greater demand on our attention. Drude divides the world into 
fourteen “ floral kingdoms,” namely—(1) Northern, (2) Central Asian, (3) Mediterranean, 
(4) East Asian, (5) Middle North American, (6) Tropical African, (7) East African 
Islands, (8) Indian, (9) Tropical American, (10) Cape, (11) Australian, (12) New 
Zealand, (13) Andine, (14) Antarctic. Most of these regions are subdivided, and the 
overlapping of the elements of different regions is indicated by lines and dots. 
As Drude himself remarks, we are all striving and devising with the same aim in 
view, and we arrive by different ways to much the same conclusions. He claims that 
he obtains practically the same results as Engler, but by different methods; that 
Engler’s scheme is, after all, based essentially on present conditions; and says that 
there is far more difference in the arguments of the writers on phytogeography than 
there is in their deductions and cartographical illustrations. This is doubtless true 
to a certain extent, because there are certain facts which no student can overlook or 
disregard ; yet it is none the less true that one begins with four and the other with 
fourteen regions, and therefore there must be a wide difference in their value and 
extent. 
Engler’s scheme, based upon a small number of primary regions, commends itself 
because these are much more nearly of equal importance than are Drude’s; but his 
old oceanic region is altogether inadmissible from the standpoint here taken, involving, 
as It does, the relegation of the Northern Island of New Zealand to one of his primary 
divisions and the Southern to another. | 
A small number of primary divisions undoubtedly offers the least difficult basis for 
further division. Equivalent regions and subregions it is impossible to define, because - 
* “Die Florenreiche der Erde. Darstellung der gegenwiirtigen Verbreitungsverhiltnisse der Pflanzen, mit 
3 Karten.” LErginzungsheft no. 74 zu Petermann’s Mittheilungen. 
+ Atlas der Pflanzenverbreitung. 
