42 INTRODUCTORY ESSAY. 
XXVIT.—On the classification of the species of Calamus. 
I must admit that I consider the systematic arrangement of . Calamus proposed by 
me to be far from satisfactory; the species are, however, aggregated in groups whose 
affinities are in most cases real and not artificial. 
The order in which the groups succeed each other is not wniseriate; that is to say, 
it must not be supposed that a group is directly derived from the one which precedes 
it. The whole series of species of Calamus in my arrangement lays no claim to rep- 
resent a true phylogenetic conspectus; indeed, I believe such a classification to be in 
reality as impossible for the genus Calamus as it is for almost any other group of 
organisms, 
I have no belief in the formation of the species of which a genus is composed 
by a gradual and successive modification from a single primitive archetype. I believe 
therefore that it would be impossible to compile a complete phylogenetic system of 
existing organisms even if we could actually examine all the transitory forms of each 
genus which may have existed, but have now disappeared. 
My hypothesis is that in the remote epoch which I have called “ Plasmatical,”? 
reproduction may have been possible even between two organisms of very diverse 
nature.* I therefore assume that a few primitive dissimilar types may have been 
eapable of producing fertile offspring, participating in the characters of their parents, 
and I do not think the manifestation of this phenomenon impossible at that remote 
epoch, if it be assumed that the power of heredity, or of that force which causes the 
transmission to their offspring of the universal qualities acquired by their parents, was 
constantly more active the further back we go in the history of the development of the 
organic world; while the “ plasmatical force," or that which has given to organisms 
the faculty of assuming new forms or colours more fitted to changed conditions of 
existence, very powerful in remote geological times, has been constantly less active 
the more we advance towards the present era, In other words, I suppose that in 
the remote past fertile hybridism may have occurred between different species of the 
same genus, between representatives of different genera and, in the very earliest times, 
even between organisms of a nature so different that now we should eonsider that they 
belonged to different families. According to this theory the connecting links between 
two species would not have been the result of innumerable forms gradually appearing by 
continuous slight variations, but would be due to the sudden intervention of hybridism. 
In my systematic arrangement of the species of Calamus l have tried to aggregate 
the species in groups in accordance with their natural affinities, but I have not been 
always able to effect my purpose, partly because in some species the affinities are not 
very clear, partly because our knowledge of some species is defective. 
If we attempt to establish the chief divisions of the genus upon the more con- 
spicuous biological characters presented by its constituent species, as for example 
on whether the leaves are furnished with, or are destitute of, a cirrus; whether the leaf- 
sheaths are flagelliferous or not; whether the seed has a ruminate or an equable 
albumen: it very often is found that we are separating widely certain species that in 
other respects are manifestly closely allied. For instance C. erectus is evidently related 
* Beccari: Nelle Foreste di Borneo, p. 300, 
