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 Neuroptera 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 Avhich 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 A r /ere waning or dying out. 



Certain Brazilian species of the lepidopterous family, 

 Zygcenidce and Bombycidce, mimic in form and coloration 

 certain butterflies, especially the Heliconidce, 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 Heli- 

 conidce, been 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: Helicomdae. Traus. Liunean Society, London, xxm. 

 1862. 



Wallace. Contributions to the Theory of Natural Selection. 1870. 

 On the Phenomena of Variation and Geographical Distribution 

 as illustrated by the Papiliouidse of the Malayan Region. Trans. Lin- 

 nean Soc., London, xxv. 1865. 



Trimen. On some Remarkable Mimetic Analogies among African 

 Butterflies. Trans. Linnean Soc., London, xxm. 1869. 



Poulton. The Colors of Animals. 1890. 



With the writings of Darwin, Weismann, Fritz Miiller, Meldola, 

 G. W. and E. G. Peckham, Butler, Beddard, Riley, Lubbock, Weir, 

 Morse, etc. 



