THE STATE ENTOMOLOGIST. • 163 



<cess, indeed, is so beautifully simple and intelligible, that, but for cer- 

 tain prepossessions and prejudices, it would at once command the as- 

 sent of every logical mind. In fact, it is strictly analogous to the com- 

 mon operation of "rogueing" abed of seedlings, which every gardener 

 is familiar with. The only difference is that, when the gardener pulls 

 up what he calls the "rogues" out of a thousand seedling tulips,^, e., 

 those which deviate from the standard of perfection which he is aim- 

 ing to attain, he acts with the definite object of preventing the further 

 propagation of those so-called "rogues;" whereas, when cannibal an- 

 imals destroy the "rogues" among the imitative butterflies, they are 

 -of course perfectly ignorant of the consequences likely to follow, and 

 act wholly and solely for the gratification of their own carnal appe- 

 tites. In short, the whole phenomenon is explained on the theory 

 <of Natural Selection as expounded by Darwin. 



Since the publication of Mr. Bates's paper, a great many addition- 

 al cases of similar mimicry among butterflies have been observed by 

 Mr. Wallace* in the Malayan region of South America, and by Mr, 

 Trimen in South rVfrica.f But though most of these wonderful cases 

 ■of mimicry occur in the tropics, where insect development is so rapid 

 and species are so abundant, we also have a striking instance of sim- 

 ilar mimicry in our two N. A. butterflies, Archippus and Disippus. 

 The resemblance between them must long ago have been noticed, for 

 it is so servile that Prof. Jaeger in his Life of North American In- 

 ■sects, has actually favored his readers with a figure of the Disippus 

 and gravely informs them that it is the Archippus butterfly. Indeed 

 it is far more striking than my figures would indicate, and in a state 

 of nature the two insects could hardly be distinguished at a short 

 distance by the sharpest eyes. The fact that these two species offer 

 an illustration of similar mimicry to that observed so frequently in 

 the tropics, was first made clear by Mr. Walsh and myself in the 

 American Entomologist for June, 1869; and the facts which have 

 since come to my knowledge all tend to confirm the opinion. 



The only other species belonging to the same genus as our Disip- 

 pus butterfly, which occurs in the Mississippi Valley, is the Ursula 

 butterfly^ (Limeniiis ursula, Fabr.), an insect which differs remark- 

 ably from our Disippus in beingof a sombre blue-black color, with its 

 wings bordered both above and below with blue, and below with a 

 series of dull orange spots inside the blue border. Its larva feeds on 

 Willow, Scrub-oak, Whortleberry, Cherry and Plum, and as already 

 stated, has the same habits as that of Disippus, which it resembles so 

 closely as scarcely to be distinguishable. The pupae of the two spe- 

 cies are also undistinguishable. 



* See the Chapter on Mimicry among Lepidoptera in his Contributions, etc. 



-j- See his paper on "Mimetic Analogies among African Butterflies," in the Transactions of the 

 Linmean bociety for 1863- 



% There are seven described species of N. A. Limenitis, but with the exception of the two above 

 named they are all confined to the more eastern or western portions of the Continent. 



