432 Darwin, and after Darwin. 
forms throughout the world, as it would be for a naturalist to 
land for five minutes on some one barren point in Australia, 
and then to discuss the number and range of its productions 1. 
In view of all the foregoing facts and considerations, it 
appears to me that the second difficulty on our list is com- 
pletely answered. Indeed, even on a moderate estimate of 
the imperfection of the geological record, the wonder would 
have been if many cases had of occurred where groups of 
species present the fictiious appearance of having been 
suddenly and simultaneously created in the particular forma- 
tions where their remains now happen to be observable. 
Turning next to the third objection, there cannot be any 
question that every here and there in the geological series 
animals occur of a much higher grade zoologically than the 
theory of evolution would have expected to find in the strata 
where they are found. At any rate, speaking for myself, I 
should not have antecedently expected to meet with such 
highly differentiated insects as butterflies and dragonflies in 
the middle of the Secondaries: still less should I have ex- 
pected to encounter beetles, cockroaches, spiders, and May- 
flies in the upper and middle Primaries—not to mention an 
insect and a scorpion even in the lower. And I think 
the same remark applies to a whole sub-kingdom in the case 
of Vertebrata. For although it is only the lowest class of 
the sub-kingdom which, so far as we positively know, was 
represented in the Devonian and Silurian formations, we 
must remember, on the one hand, that even a cartilaginous 
or ganoid fish belongs to the highest sub-kingdom of the 
animal series; and, on the other hand, that such animals are 
thus proved to have abounded in the very lowest strata 
where there is good evidence of there having been any forms of 
life at all, Lastly, the fact that Marsupials occur in the Trias, 
1 Origin of Species, 282-5. 
