PROTECTIVE RESEMBLANCE. 679 
ery of red and blue, hops about in the day-time, and, as he 
proved by experiment, is thoroughly distasteful to fowls 
and ducks. 
We have seen that many animals resemble externally those 
above them in the scale of life ; in the synthetic or general- 
ized types from which the more specialized forms have prob- 
ably originated, there are characters which cause them to 
resemble more recent, new-fashioned types. It is possible 
that in many cases the older types, doomed as they were to 
destruction, have had their existence prolonged by their 
protective resemblance to modern types. 
For example, the Newroptera as a group are geologically 
of high antiquity ; owing to geological extinction, but few 
species, compared with those of other orders, have survived ; 
and those which are now living often resemble members of 
higher, more recent orders. The inference is, then, that 
the mimickers have survived by reason of their resemblance 
to the more abundant forms which appeared, as the more 
old-fashioned types were waning or dying out. 
Certain Brazilian species of the lepidopterous family, 
Zygenide and Bombycide, mimic in form and. coloration 
certain butterflies, especially the Heliconide, which abound 
in Brazil. The former groups are evidently the older geo- 
logically, as there are wide gaps between the genera; and 
the indications are that these butterfly-like moths have 
likewise, from their resemblance to the more abundant Helv- 
conide, heen preserved. It thus appears that protective 
mimicry may be an important factor in the preservation of 
species. 
LITERATURE. 
Bates. Contributions to the Insect Fauna of the Amazon Valley. 
Lepidoptera: Heliconide. Trans. Linnean Society, London, xxumz. 
1862. 
Wallace. Contributions to the Theory of Natural Selection. 1870. 
—On the Phenomena of Variation and Geographical Distribution 
as illustrated by the Papilionidee of the Malayan Region. Trans. Lin- 
nean Soc., London. xxv. 1865. 
Trimen. .On some Remarkable Mimetic Analogies among African 
Butterflies. Trans. Linnean Soc., London, xxii. 1869. 
Poulton. The Colors of Animals. 1890. ; 
With the writings of Darwin, Weismann, Fritz Miller, Meldola, 
G. W. and E. G. Peckham, Butler, Beddard, Riley, Lubbock, Weir, 
Morse, etc. 
