July, 1915 . The Queensland Naturalist. 
13 
attained a maximum and then sank into comparative ob- 
scurity ; the second is the revelation that the necessities of 
existence sometimes made progress a development from the 
compjlex to the simple— a reversal of the general plan.” 
To these concise extracts illustrating the comj')lexities 
of evolutionary processes, one might add the evidence for 
man himself. It seems probable that nature tried her 
prentice hand several times before man, as we know him 
to-day, developed from simian ancestors. Certain fossils, 
such as the well-known Pithecanthropus erectus, are almost 
more ape-like than human. But we find also varying types, 
some of which ai)parently i*epresented races which died out 
and left no ancestry. Remains have been found of early 
men with comparatively large brains, of long-headed and 
broad-headed men, of men with small teeth and of men with 
large, of almost chinless forms, and of one lower jaw with a 
remarkable chin. Thus, many anthropologists are suggesting 
that the human race evolved from more than one primordial 
stock. Our genealogical tree may be less simple than was 
once thought. 
To take an Australian instance, let us glance at our 
extinct marsupial fauna. \^ery many of these are in no way 
direct ancestors of the forms we know to-day. The immense 
Diprotodon. with its five-toed feet, its dentition somewhat 
similar to that of the kangaroo, and its wombat-like limbs, 
may not be regarded as lineally associated with any representa- 
tive of our modern fauna. It surely represents one of the 
great lateral off-shoots from the marsupial life of Tertiary 
times, and it apparently left no offspring for posterity. 
Yet there are associative, or, to use Huxley's term, inter- 
calary types, such as Nototherium, Euowenia, and Phas- 
colonusj'^^ which connect this bulky animal with the modern 
wombat and other forms, all of which had a common origin. 
I would not like to designate Thvlacoleo carnifex, the so- 
called marsupial lion or hyaena, as a lineal ancestor of any 
of our present Phalangers, and the same remarks might be 
applied to one or two other extinct genera. There are, of 
course, fossil representatives which show definite and lineal 
relationship with our present species, and some are obviousU^ 
but slightly different forerunners. But we see that in Australia 
our animals, though largely isolated, were not merely marking 
time all through the ages. Life radiated out and specialised 
forms appeared, many of which failed to survive. Our 
past and present indigenes are not merely representatives 
of the pre-placental, primitive mammalian fauna which was 
probably almost world-wide in Mesozoic times. Evolution 
has taken place here as well as elsewhere, and there are 
evidences both of progress and degeneracy. 
(7) Phascolonus Gi^as now includes Sceparnodon Ramsayi : Sterling! Mem 
Roy. Soc. South Aus., vol. I, p. IV. 
