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P IN the Andean heights of the De. selected the one most convenient to the
partment of Antioquia, Republic of camp for beginning our work. The bed of U Colombia, there is a climatic stra- this power stream held an average angle of tum marked by a uniformly cool temperature thirty-eight degrees from the horizontal and, and great humidity. The rainfall is enor- for a considerable distance, slipped down mous in quantity. The topography included over the smooth surface of the worn rocks within the stratum is mountainous in the in a thin broad sheet. extreme. The streams are many and tor- Our first efforts were directed toward as. rential in character, and their waters rush certaining the volume of flow of the stream. roaring down the steep and tortuous channels To do this it was necessary to introduce a to the placid rivers of the plains below- measuring weir at a point above the takethey are but a series of falls, cascades, and off of the plant. The weir was soon estabblustering "riffles," The country rock is lished and the deflecting dams were built in. schistose in character and comparatively When the water was turned, a part of the soft and the erosion of the stream beds is bed of the stream lay uncovered, exposing very rapid.
a couple of old gravel-filled potholes. Since Ancient stream beds high up
such potholes not infrequently contained cañons' sides are pitted with many potholes gold, my brother proceeded to dig out one of unusual interest to the student of lynamic of them while I was engaged in taking the geology. There is not a waterfall in the readings from the weir. region today so small or insignificant that He had been at this task for only a few it is not busily engaged in boring out a minutes when he called out to me: more or less cylindrical hole in the rock be. “Say, here's a fish.” neath. The falling water at the point of I replied saying something about his “seeimpact seems inevitably to set up a rotary ing things,” and proceeded to expatiate upon motion, carrying stones, sand, and gravel the impossibility of his finding a fish in such around with it, and the resulting wear bores a place, and upon the utter inability of any out the pothole.
fish, even among the best swimmers, to surInto these potholes falls the drifting, gold
mount the difficulties of such a stream. bearing quartz with which the upper Andean I pointed out the absurdity of imagining regions abound, and within these mills of a fish swimming with nine-tenths of its body nature it is ground to an impalpable pow. out of the water, as it would have to be, der, and the gold freed from its matrix finds up that part of the stream where the water lodgment in the gravels and the alluviums passed in a thin sheet over the smooth rocks. of the plains and the river bottoms.
“He'll have to be an aviator,” I said. So the lure of the gold that indirectly drew my I pooh-poohed the idea recklessly. brother and myself so far into the jungle- Harry listened with suspicious patience to jungle that answers the most rigid definition my lengthy dissertation, while I, from a of the term.
theoretical standpoint, utterly demolished his We were employed to install a hydroelec- wuthinking assertion, then he blurted out: tric plant to be used in connection with the "Well, are you all through? Here's the operations of a company engaged in placer fish! This is a fact, not a theory you've mining. A permanent camp haid been es- kutted up against.” tablished in niches cut in the steep sides He held in his hand a living fish, and a of the cañon and was located at an elevation catfish at that, resembling the catfish or of 115 feet above the roaring Santa Rita horned pout of the North. I took it and Creek.
looked it over. There it was, a real live Since power streams were numerous, we fish, nearly a half foot long. There could be
1 "Xotes on the Habits of a Climbing Catfish (Arges marmoratus) from the Republic of Colombia," By R. D. 0. Johnson, Annals New York Academy of Sciences, Vol. XXII, pp. 327-333, December 20, 1912.
no possible doubt about it, in spite of the utter impossibility of the thing.
Harry had his laugh and returned to his digging. I was completely puzzled—but I had pressing work to do. I carefully placed the fish in a small pothole at one side. This hole was about four inches in diameter and twelve inches in depth and held perhaps two or three inches of water. Catfish are hardy, so I figured that there was enough water to last this little fellow until I could give him more attention.
After I had finished my work at the weir, I returned to the little pothole to give that amazing fish a closer scrutiny.
He was not to be found, so I called out, “What did you do with the fish, Harry ?"
Harry asserted that he had not taken the fish and that he had paid no attention to it. That certainly was a mystery. I did not think it possible for a five-inch catfish to jump out of a four-inch pothole twelve inches deep. I concluded, however, that that was the only way of escape and contented myself with this rather lame explanation.
Before we returned to the camp that afternoon, Harry had caught two "cats” in another pothole. These we ried down to the camp in our dinner pail. We arrived at the camp just as the late afternoon meal was being served. I hastily poured the water and the fishes from the dinner pail into a three-gallon galvanized bucket and set it in an inconspicuous place outside the kitchen. After dinner I sought the bucket to get a better look at the fishes which had destroyed a good theory. They were not in the bucket. I inquired of several who might possibly have freed the fishes but no one knew anything about them. This mystery was getting too thick for comfort.
The next day I made a special trip up the power stream and managed to secure two more of these fishes. I brought them down to camp and placed them in the same pail that had held the others and sat down to watch their maneuvers.
For a time they were content to swim about, butting their blunt noses against the sides of the vessel. Then, to my amazement, one of them thrust its "nose" out of the water and began creeping up the side of the pail. I watched it hitch itself up by short longitudinal movements until it had reached the top edge and fell out
side of the bucket. I put it back and watched the performance repeated. Then I transferred one to a tall glass jar and through the glass watched the operation of the creeping mechanism. I caught others and dissected them and studied them until I was in possession of their secret.
This lies in the combined action of two sucking mechanisms. One of these is the ordinary sucker mouth, surrounded by a soft flap, very thin and flexible at the edges. The other is an interesting structure consisting essentially of a bony plate beneath the skin on the under side of the fish where the ventral fins are attached. These fins are broad and flat and their surface is studded with small sharp teeth pointing backward. The bony plate is given a shuttle action by muscles attached fore and aft so that the fins may be moved lengthwise of the fish through a distance equal to about one sixth its length. With this apparatus the fish is able to create a suction pressure, and by means of the alternate action of the two suckers, it is enabled to crawl, inchwormlike, on a smooth vertical surface.1
Shortly after this, the mining company undertook the cleaning out of a large pothole which was eight feet in diameter and twenty-two feet in depth. Before the bottom had been reached, the water that remained in the pothole was found to be full of these climbing catfishes. They were naturally greatly agitated by the action of the workmen who were shoveling out the gravel. Several times
of them started to climb out but were frightened by the men and dropped back. I surmised that as soon as the work was stopped for the lunch hour these fish would essay the long climb to the top. I was not mistaken and my watch
1 The climbing catfish which Mr. Johnson describes is not the only species of fish which is able to climb by means of its ventral musculature. In the Himalaya Mountains--so similar to the Andes in ruggedness--there occur several species which have adapted themselves in various ways to this environment. Nemachius rupicola and per. haps other species of mountain cyprinids adhere to the rocks by means of their smooth, ventral skin and enlarged lips. The silurid genera Pseudechencis and Glyptosternum cling by means of a well developed abdominal sucker. The mountain torrents of the Himalayas form the nursery for many species of frogs. Their tadpoles, like the fish, have become adapted to these terrific floods, Some of the tadpoles, such as Megalophrys parna, cling by means of their lips and the ventral mus. culature, while other species, such Rana afghana, possess a well developed ventral sucker,
-G. K. N.
ing was rewarded by seeing four climb up a distance of eighteen feet to the pool of water above. They followed a thin film of water that trickled down the rock. This water kept their gills wet and sustained them on a climb that must have been arduous. It required half an hour to make the ascent.
To my own satisfaction I had answered the question of how it was done; there remained the question of why. The fish was evidently a case of extreme modification and adaptation to fit a peculiar environment. Some catfish do not climb, why should these? An analysis of the environment brought the answer.
I found that the Andean torrents were the habitat of myriads of these curious creatures, “capitanes" they are called by the natives. The individuals I had examined were living in a torrential stream almost daily subjected to the sudden fury of sweeping floods. The violence of these floods is unimaginable to one who has not witnessed
them. It seems that nothing unanchored in the stream bed can withstand their wild energy. As swimmers, however, these fishes are clumsy and inept. To witness their awk. ward, wriggling, swimming movements is to know at once that they could not by that means of propulsion alone make any headway against even moderate currents.
We can understand that to remain at home in time of flood, these denizens of the wild waters anchor themselves by means of their sucker mouths. Yet these catfishes are to be found in all parts of the streams, from the slender spring branches of the high mountains to the sluggish rivers of the plains. Travel they must and by using the climbing mechanism I had seen operate-the alternate action of mouth and ventral suction plate. That they are able to surmount even great falls is evident from their presence in the Santa Rita Creek, for this stream falls into the Santo Domingo River over a precipice more than two hundred feet in height.
MR. EDWARD D. ADAMS has presented to the American Museum the oil painting of the solar eclipse of June, 1918 (reproduced in color in this number of NATURAL HISTORY), by the artist, Howard Russell Butler, N.A. It is the first time in the study of such astronomical phenomena, that the colors of the corona and its prominences have been observed by a trained artist, and recorded at the moment, eliminating the chance of inaccuracy. In connection with this most remarkable painting Mr. Adams writes of the especial interest attached to the 1918 eclipse from the fact that observations of it were confined to the area of the United States. It is true also that it was observed only by people of the United States and Canada, as the great war prevented foreign astronomers from coming to this country to witness the event. The resemblance of the flame at the tip of one of the prominences to the outspread wings of an eagle prompted the association of the eagle with the astronomical event (it was just at the time of the victorious advance of the American and Allied armies) and suggested the use of the term "eagle prominence" in referring to the corona of the eclipse of 1918.
LAWRENCE M. LAMBE, the well-known Canadian palæontologist, died of pneumonia on March 12, 1919. He had been on the palæontological staff of the Canadian Geo. logical Survey for thirty-five years, and for the last fifteen years had devoted especial attention to vertebrate palæontology. In recent years he had come to be regarded as one of the leading authorities on dinosaurs. When the Geological Survey collections were moved to the Victoria Memorial Museum at Ottawa in 1910, he took charge of the fossil vertebrates and succeeded in building up a remarkable collection, especially rich in the Cretaceous dinosaurs of Alberta. In securing this fine material he availed himself of the aid of the veteran American collector, Mr. C. H. Sternberg, and of his sons. The American Museum staff has followed with interest the work and
of Mr. Lambe, as he studied vertebrate palæontology in 1903 under Professor Henry Fairfield Osborn and learned here much of the field technique and methods of research which he applied to Canadian palæontology with such notable results. His unexpected death in the midst of a busy and successful career comes as a shock to his many friends and as a
THE New York Aquarium is to have constructed a seaworthy well boat for purposes of marine collecting. Such a boat with a 10 x 11 foot well for preserving the fish alive will make possible hereafter the transportation in good condition of not only the local fish of Long Island shores but also the tropical species that migrate in summer up the Gulf Stream, and other large fishes re. ported taken in the trap nets of local fish
The Tropical Research Station of the New York Zoological Society in British Guiana has reopened for scientific investigation, after a lapse owing to the absence of most of the staff with the American Army. Mr. C. William Beebe, the director, sailed for Bartica on February 26. Bartica is favorably situated for the study of both fauna and flora and its climatic conditions are ideal for the work. General ecological investigation will be made on the relations of plant and animal life in the jungle while special work will be carried on by individual investigators. Professors William Morton Wheeler, of Harvard, Ulric Dahlgren, of Princeton, and Alfred Reese, of West Virginia, will make special study of ants, electric fishes, and crocodiles, respectively, while Director N. L. Britton, of the New York Botanical Garden, will make a survey of the forests. The New York Zoological Society assumes the financial support of the project through the generosity of five members of the board of managers, Colonel Anthony R. Kuser, Messrs. C. Ledyard Blair, Andrew Carnegie, George J. Gould, and A. Barton Hepburn.
An example of the development of modern museum methods of instruction in connection with university work is shown in the expansion of the museum of the University of Illinois. The plan includes, in zoology, both general synoptic series illustrating the principal forms of animal life, living and extinet, and ecology groups, such as life in and about an old decaying log of the local woods. The first of a series of economic groups to show the presence and activities of common insect pests is also completed.
DR. LIVINGSTON FARRAND, president of the University of Colorado, formerly professor of anthropology in Columbia University (in 1903-4 assistant curator of ethnology in the
THE fight of the entomologist against insect pests has been greatly increased during the war.
Dr. L. 0. Howard, chief of the Bureau of Entomology at Washington, has recently reviewed the work of his Bureau and of the subcommittee on medical entomology of the National Research Council. The
SHARK LIFE IN THE WARM WATERS OF THE SARGASSO SEA
The Blue-shark Group, recently completed at the American Museum, was modeled from a cast of a female shark formerly on view at the New York Aqua-