Butterfly Specimens Research Articles

First Postwar Specimens of Butterflies sent from the USSR

First Postwar Specimens of Butterflies sent from the USSR

Natural theology and nature's disguises

Henry Walter Bates’s paper on the phenomenon of mimicry in butterflies’ was read at the Linnean Society of London on November 21, 1861-three days short of the second anniversay of Darwin’s publication of On the Origin of Species. In this paper Bates described surprising resemblances among butterfly specimens of different families. He explained these similarities of coloration and pattern on “Mr. Darwin’s principles,” accepting both the general principle of evolution and the mechanism of natural selection. Without equivocation, he wrote, “I believe the case offers a most beautiful proof of the truth of the theory of natural selection. It also shows that a new adaptation, or the formation of a new species, is not affected by great and sudden change, but by numerous small steps of natural variation and selection.“2 According to Bates, natural selection had been acting over a long span of time, allowing for the gradual acquisition of a deceptive appearance in Leptalis butterflies, ordinarily a prey for many insectivorous birds. The mimicking Leptalis looked very much like the Heliconiidae, a family of butterflies which contained a number of species that were distasteful to many birds; Leptalis consequently were spared predation, once birds learned the pattern to avoid. The beautiful analogy of

Postglacial Invasion Routes of Canadian Arctic Butterflies

Several thousand specimens of arctic butterflies were accumulated in the Canadian Northern Insect Survey. When the distributions of the various species were recorded and plotted on a map, some evidence appeared that these insects entered Canada in postglacial times from the northwest, and from the south. There is also some evidence that a few may have come from the north. The most common invasion was from the northwest, and it appears that some, such as Erebia youngi Holl., probably entered Canada rather recently, as it is only known to occur in the Yukon. Boloria pales D. & S. occurs from the Yukon to within about 150 miles west of Hudson's Bay. Colias boothii Curt. occurs as far east as Southampton Island, and Erebia rossii Curt. is distributed to Baffin Island. Others such as Boloria polaris Bdv. have spread to northern Quebec and Labrador. Thus it appears that there are successive stages of distributional spread from the northwest.

Important Collections for Harvard Museum

Two great collections have recently been added, according to Science Service, to the Museum of Comparative Zoology at Harvard. John Eliot Thayer has presented his series of thirty thousand specimens of bird skins, forming probably the finest private collection of North American birds. The collection also contains many thousands of nests and eggs. Some of the specimens are very valuable: extinct birds include the Labrador duck, the Eskimo curlew, and the passenger pigeon. There are ten eggs of the extinct great auk, and several of the California condor, which is becoming very rare. The second collection, bequeathed by Andrew Gray Weeks, contains some 75,000 specimens of butterflies and moths, many being type specimens. The former owner also left to the museum a fund for the care and increase of thecollection.

Geographical Notes

MOUNT RORAIMA, in British Guiana, was ascended for the third time on October 14 last, by Mr. F. Dressel, an English orchid collector. The first ascent, it will be remembered, was by Mr. Im Thurn, in December 1884. The second was in November 1886, by Mr. Cremer, also an orchid collector. Mr. Im Thurn's ascent took place in the beginning of the wet season, when everything was saturated with moisture. Mr. Dressel ascended after continuous dry weather, and found the upper surface comparatively dry, the elevated portions most markedly so; while large areas of the sward-like levels were perfectly desiccated. The water in the various channels was very shallow, and the deep basins or depressions contained but very small quantities, though in no case was any found to be quite dry. Frequently the surface of the water in these shallow basins was more or less covered with a green, apparently a Confervoid, layer. In the pools at the bottom of these wide basins, Mr. Dressel found a considerable quantity of quartz, in the form both of separate crystals, and of aggregated masses, of various and often of large sizes. The presence of such quartz in such positions and under such conditions, Timehri points out, is an extremely interesting fact, though our want of knowledge of the petrographic character of the formation of the top of Roraima, beyond the fact of its being sandstone, renders it barren, and one hardly justifying speculation. It will be remembered that on the first ascent no animal life was noticed during the short time spent on the top; and this necessarily denoted the likelihood of the absence or great rarity of birds and insects. During the two or three hours spent on the top by Mr. Dressel, no birds were seen; but a few specimens of butterflies, all of one kind, of a dark brown and nearly black colour, were observed, and two of them were caught, though one alone was sufficiently preserved to show much of its structure. In the shallow basins a few forms of a small black toad with a yellow spot on the throat was also seen, and one was caught, but was accidentally left on the top. A third animal form was found in the moist earth attached to some plants which had been pulled up; from Mr. Dressel's description it is conjectured by Timehri to be a Millipede, allied to Julus. It is probable enough that a stay of a day or two on the top would well repay the naturalist; and Mr. Dressel thinks it would not be difficult to arrange for such a stay. The fantastic shape into which the sandstone has been fashioned, and the weirdness of the scenes which have been so graphically described by Mr. Im Thurn, affected Mr. Dressel in a similar manner. He mentions that the surface of the rocks present very closely the appearance of granite, owing to weathering; and at first he thought some mistake had been made in describing the formation as sandstone, until he moved away a small rock from its setting, when its real nature was revealed.

FOSSIL BUTTERFLY FOR SALE

In order to illustrate more fully his forthcoming work on New England Butterflies, the undersigned offers for sale for Two Hundred and Fifty Dollars, that wonderfully preserved Fossil Butterfly, Prodryas Persephone, of Colorado. The accompanying cut gives a rude impression of it. Less than twenty specimens of fossil butterflies are known in the world, and this is by far the most perfect and best preserved.