here in the spring seem to be in rather too good a condition to have made the journey. On the other hand no specimens have been found in this vicinity in the winter and as adults are fairly common in May, it is just as hard to believe that they did not come up from the South.

Long flights of butterflies and moths are not rare. One of the longest was put on record by Frederic A. Lucas in 1887 when he saw many Lepidoptera, chiefly moths, one thousand miles off the coast of Brazil. Such flights however are not migrations in the true sense. These insects had doubtless been blown out of sight of land and had simply kept on flying because of necessity.

The migratory locust is not a similar case for it moves in swarms only when the birth rate has been so large that the local food supply is exhausted. The adult monarchs are certainly not hard put to it for food as not only are flowers abundant when the migration starts but also adult butterflies take but little nourishment at any time. The so-called migration of the maggots of certain fungus-gnats (Sciara sp.) is, naturally, extremely limited and would not be noticed were it not that they are gregarious in habits. This too, is a movement in search of food. The swarming and migration of the monarch1 remain a mystery in spite of the fact that they occur all about us every year.

Possibly it is on account of these roaming habits, possibly it is also on account of its protection from birds, that the monarch butterfly is now spreading over the entire earth. It has found its way to Australia, Java, Sumatra and the Philippines. A few specimens are found every year in Great Britain where the entomologist's net is an enemy not to be daunted by gaudy color and acrid taste. It is well established at the Cape Verde Islands and will without doubt shortly have conquered the earth.

1 What is one of the most interesting, perhaps the most astounding and certainly the most inexpensive group for its size ever prepared in the American Museum has newly made its appearance in the hall of insect biology. It shows a three-foot square of ground on which grows a small white oak tree and the season is early autumn as announced by a few sprigs of white aster. The astounding sight is the presence of some five hundred of one of our largest North American butterflies clinging everywhere to leaves and twigs. This five hundred is reported by those who have witnessed the swarming and what seems to be the migration of the monarch butterfly to be a very small part indeed of the numbers that actually come together. They gather from miles about. Fifty or more can be caught by one sweep of a small net over the leaves where they rest, while those not captured but dislodged by the movement of the net are for number like a storm of falling leaves as they flutter and poise to settle lightly back on the tree. Tall slender sprays of goldenrod and aster, gradually hidden under burdens of folding and unfolding brown wings, finally bend to the ground under the weight - a fact by the way that gives a vivid idea of numbers, for weight effective in any degree is not associated in our minds with butterflies. In the swarming at Clinton, but a stone's throw from the sea beach, the butterflies gathered on the oaks and hickories to a height of twenty-five or thirty feet, on the sheltered sunny side of the grove. They were there one day and gone the next, following the coast southward.— Editor.

THE "SHOVEL-PIT" AT ELY, NEVADA

REMARKABLE SURFACE COPPER MINING SHOWN IN A LARGE CANVAS RECENTLY PRESENTED TO THE MUSEUM BY THE NEVADA CONSOLIDATED COPPER COMPANY

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By L. P. Gratacap

UREKA Cut at Ely, Nevada, referred to by the engineers of the

Nevada Consolidated Copper Company as the "shovel-pit," is

to-day a gigantic trench excavated in the side of a mountain. Terrace by terrace, it is gradually enveloping and destroying this mountain and when the destruction is accomplished the shovel-pit will assume the shape of an enormous basin about one mile long, one-third of a mile wide and three hundred to four hundred feet deep, a topographic feature of such magnitude that if not in a region of restricted rainfall, it might slowly accumulate waters and become a lake. Sulphides of copper, as also of iron, are scattered throughout the mountain mass and although the percentage of copper is only one to three, or about seven hundred ounces in a ton of rock so that the amount of metallic copper in any cubic foot is insignificant, the total amount that can be extracted from the mountain reaches great dimensions, probably many thousands of tons, a billion and a half or more of pounds.

The Nevada Consolidated Copper Company through its president, Mr. S. W. Eccles, has presented to the American Museum of Natural History an enlarged painting of this remarkable property. This painting is displayed on the south wall of the hall of minerals and was executed by Albert Operti. In his treatment of the subject he has adopted the French school of color and technique, producing a canvas which harmonizes admirably with the hall. While strictly maintaining the correct geological features throughout, closely following panoramic photographs and engineer's plans, Mr. Operti has at the same time not omitted artistic atmosphere, holding before himself the difficult problem of uniting illustrative with æsthetic values.

The region in which this copper property is situated has been one of extended and not always successful exploitation, and to-day its metallurgical values are practically confined to the two important mining companies at Ely, the Nevada Consolidated and the Giroux. The orebodies are found along the Robinson Cañon where evidences of the disasters that attended the earlier mining enterprises are visible in deserted smelting works, the smallness of whose slag dumps betrays the failure of premature hopes. The earlier operations continued intermittently for some years, until M. L. Requa and F. W. Bradley of San Francisco, recognizing

A new canvas in the hall of minerals the "Shovel-Pit" of Ely, Nevada. This was painted by Albert Operti and presented to the American Museum by the Nevada Consolidated Copper Company through its president, Mr. S W. Eccles

the wide dissemination of the copper ore, were led into a calculation of the ultimate magnitude of the resources of the area. Prof. Andrew C. Lawson

of the University of California made a geological survey of the district, and under the guidance of his conclusions, these capitalists secured the more promising grounds. The company became well financed and aggressive mining was pushed with astonishing results.

As to the geology of the Robinson Cañon, the region is a limestone formation into which, at a long distant time in the past, bodies of molten rock have penetrated bringing with them copper minerals which have remained both in the intruding rock and in the limestone, especially on the south side of the cañon. These copper minerals are for the most part sulphides, although the action of the water carrying oxygen has through many sections of the hills converted the sulphides into carbonates (green malachite), and the lower layers of the formation have also from the beginning been slowly enriched by having transferred to them the copper contents of the overlying beds. Sulphides with a low percentage of copper have in this process been changed or mixed with sulphides of a higher percentage and this secondary zone of enrichment as it is called, contains the most valuable ore. Below this again are the primary beds which have not been enriched in this way and whose mining becomes a question for metallurgical economics.

The work is carried on through the agency of powerful steam shovels

Terrace by terrace this surface copper mining is destroying a mountain from which eventually will be extracted many thousands of tons of copper, probably a billion and a half of pounds. The canvas shows the workings as they were in 1910

which plow up the more or less shattered rock and dump it into trains of ore-cars, which again transfer it to the concentrators and smelters some twenty miles away. The system of work consists in stripping off the surface, which is practically barren of ore, in order to uncover the ore bodies below, the operations involving the construction of a series of ascending terraces. on which the process of mining or stripping is continued simultaneously, with the highest always the most advanced in the work.

The painting represents the state of the workings in the summer of 1910, and displays instructively the relations of the geological elements to one another. The deserted diggings on the extreme left show terraces carried around an amphitheatre-like excavation through shattered rock containing the iron and copper oxides, and the commingling stains indicate the confused association. The center of the painting shows the broad convex breast of the hill which is the present focus of mining activity. The terraces rise seven stories with an equipment of cars, steam shovels and miners, and show distinctly the yellow stripping representing barren surface material to be carried by cars to the wash dumps, and the grayish white exposures underneath constituting the ore bodies to be mined with steam shovels and sent to the concentrator at McGill about twenty-two miles away. The train of cars on the extreme right is loaded with the crushed ore, described as looking like "crusted sugar," and the tracks lead away to the smelters.

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A PYTHON FROM THE PHILIPPINES

By Mary Cynthia Dickerson

N authentic story touching a twenty-four-foot python's capacity

for swallowing prey comes from the Philippines. Laborers found

the snake on an estate near Iloilo, Panay, when on their way through

Photograph of wild boar swallowed by Philippine regal python. It was estimated to weigh 125 pounds. New York Zoological Park authorities assert that judging from the size of bones found in the stomachs of newly received pythons, a twenty-four-foot regal python could swallow a boar of 150 pounds