Is there any information on the Arcla an alleged odd-looking arctic animal with strange tracks like grooved pavement or cobble-stones and whether it exists?

Answer 1

In chapter XII of Marshall B. Gardner's "A Journey to the Earth's Interior" of 1920 there is a passage that mentions the arcla. It is here reproduced:

"That some of the animal denizens of the interior world are species quite unknown to us will not seem at all strange when we think of the conditions that obtain there, and if that were the case it would not be so very strange if at times a specimen of some kind of these unknown creatures wandered out over the lip, perhaps carried by a glacier, and was seen by some inhabitant of the far northern regions. As a matter of fact there is just such a case recorded by J. W. Buel in his survey of scientific and exploratory progress entitled "The World's Wonders". He quotes Captain Hall, who lived among the Eskimos for five years, who says that this and similar stories are worthy of credence because strange things that the Eskimos have told on other occasions have been verified afterwards. "It seems that the Eskimos often described to Captain Hall an animal which they, called the arcla: "but which is not mentioned in any book of natural history, nor did he ever see a specimen himself. . . ." The natives speak of this animal as being larger than the bear, and as very ferocious and as much more difficult to be killed. It has grayish hair, a long tail, and short thick legs, its forefeet being divided into three parts, like the partridge's, its hind feet are like a man's heels. When resting it sits upright like a man. A Neitchille Innuit, crawling into a hole for shelter, in the night, had found one asleep and quickly despatched it with his knife. It may be added here that Ebierbing, who was Hall's interpreter, now residing in the United States, confirms such accounts of the arcla, and says that the animal once inhabited his native country on Cumberland Sound." Gardner's book can be found online by following the link below. There is no evidence to the existence of the arcla outside of the above account.