150 PEOF. E. HULL, ON THE SPEEAD OF EXISTING ANIMALS 
marine origin referable to the Upper Miocene age occur on the 
small island called Santa Maria.* 
These islands are remarkable for the number and variety of 
birds and insects. According to Wallace, there are 53 species 
of birds, a large proportion being aquatic and waders — and he 
considers that many of the birds were carried by icebergs from 
Europe during the glacial period. Without denying the 
possibility of so unusual a mode of bird-migration, it may be 
doubted whether icebergs from the European area were ever 
carried into Tropical regions of the Atlantic during the glacial 
period, or that birds could have survived such a voyage — on 
such a raft. 
As regards the insects, Dr. Wallace considers that the 
butterflies, moths and hymenoptera — which are all of European 
species — have been introduced in the same manner as the birds ) 
Beetles are numerous, and out of a total of 212 species, 175 are 
European, and of these 101 appear to have been introduced by 
human agency. The remainder are indigenous, and of these 23 
species have been introduced from Europe directly by human 
agencyf. As for the rest he accounts for their presence by 
“ gales of wind” or “ drifting safely for weeks over the ocean,” 
buried in the stems of plants or “ in the solid wood of trees in 
which many of them undergo transformations.”* After this 
where can imagination regarding natural agencies stop ? 
It is with such reasons as these that Wallace endeavours to 
satisfy his mind regarding the presence of birds, including 
waders, in the far-off islands of the Atlantic — the reason being 
that he is a firm believer in the persistency, or permanence, of 
the deep oceanic floors, and rather than entertain the view that 
ocean beds have been elevated and lowered in very recent geo- 
logical times, he falls back on most improbable phenomena in 
order to account for recognised facts. It was far otherwise with 
Lyell, who had no such preconceived ideas, who recognising how. 
* Island Life, p. 240. Wallace’s statement that there are no terrestrial 
vertebrata is clearly untenable. Lyell also was under the impression that 
the only indigenous representatives of the mammalia present in the 
Atlantic islands were bats, which we know have great powers of flight, 
for he says, “During this period (Pleistocene or human) no mammalia, 
not even of small species, excepting bats, have made their appearance, 
whether in Madeira and Porto Santo, or in the Canarian group.” 
Antiquity of Man , p. 497. The names on Solari’s map clearly show that 
the views both of Lyell and Wallace were mistaken, 
t Ibid., p. 245. 
J Ibid., p. 246. 
