DISTRIBUTION AND CLASSIFICATION OF ONYCHOPHORA. 403 
What, then, are the important lessons which the distribu- 
tion of the species of the genus Peripatus teach us. They 
are, I take it, two in number :—(1) The geographical groups 
of species are natural zoological groups, the members of 
which are more closely related to each other than to those 
of the other groups. (2) The distinguishing specific cha- 
racters are distributed in an entirely haphazard manner in 
the different specific groups, so that it is quite impossible to 
show the phylogenetic affinities of the specific groups by any 
tree-like arrangements. 
On the first of these two points I have already said enough ; 
enough, I hope, to convince all candid minds of its truth. 
On the second it is necessary to dwell a little longer. Let me 
take the case of Ho-Peripatus, which is associated by 
Bouvier with Neo-Peripatus in his family Peripatide. It 
borrows, so to speak, its large and yolked ovum from 
Austro-Peripatus; the number of its spimous pads from 
Neo-Peripatus; its inner jaw, the position of its genital 
opening, its receptacula ovorum, its skin pigment from Neo- 
and Congo-Peripatus; its receptacula seminis, the length 
of the unpaired part of the vas deferens, the form of the 
spermatophore from Congo, Neo-, and Austro-Peripatus; 
the opening of the accessory glands of the male from Congo- 
Peripatus; and lastly, the well-developed coxal organs 
from Congo- Neo-, and some of the Capo-Peripatus. And, 
in addition to this mingling of characters of other groups, it 
possesses the following peculiar features found in no other 
species: the position of the nephridial opening of legs 4 and 
5, the number of distal pedal papille, and the complete fusion 
of the two ovaries (No. 9a). 
Or again, let us take Congo-Peripatus, which is associated 
by Bouvier in the same genus as Neo-Peripatus. It has 
only borrowed one character exclusively from Neo-Peripatus, 
viz. the position of the nephridial openings on legs 4 and 6. 
It has borrowed the opening of its accessory glands and crural 
glands from Ko-Peripatus ; its inner jaw, the position of its 
genital opening, its receptacula ovorum, its skin pigment from 
