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Rh pond whence the visitor came. He has observed fresh-water perch behaving in a similar manner. A further proof of the communicative capabilities of fish is afforded by the manner in which they oftentimes avoid the snares spread for them by men. They not only possess a keen sense of danger, but must have the power of warning one another. Mr. Carter feels confident, from the result of his observations, that coarse fish are able to influence one another, and if this is the case with them, why not with others? "It can not be credited," he says, "that Nature has denied to fish what she has freely bestowed upon all other animals, and therefore I think the further we go into the subject the more we shall realize that the gift of communication has been implanted in the nature of every creature to a greater or less degree."

A Link between Invertebrates and Vertebrates.—Mr. W. Baldwin Spencer, of the University Museum, Oxford, in studying the anatomy and histology of the lizard-like reptile Hatteria punctata, found on the pineal body and under the parietal foramen, a rounded mass, provided with a well-marked nerve, which is evidently an eye. A depression of the skin of the head occurs immediately above the parietal foramen, but does not lead down to this structure, which is filled up with a plug of connective tissue that is specially dense around the capsule that envelops the eye. The capsule is also filled up behind with connective tissue, in which a blood-vessel, entering with the nerve, divides and ramifies. "It becomes extremely difficult," says the Rev. W. H. Dallinger, remarking on this discovery, "to conjecture what can be the use of so curiously placed, and at the same time so highly complex, an organ; an eye so buried in its capsule and surrounding tissue, and so covered with the skin of the head as to make it almost inconceivable that it can be affected by even the most intense light; an eye placed, moreover, in a position that suggests no advantage to the present organism." It is also placed in the head of animals well endowed with the normal pair of vertebrate eyes; and on examining it in different lizards it is found in different stages of uselessness, in some being quite isolated from the brain, and in others, as in this Hatteria, having a distinct nerve-connection with the hinder part of the pineal body. "The inference, therefore, appears inevitable that it is an atrophied organ; an organ which the evolutional modifications of the original animal possessing this single eye have rendered in the course of ages devoid of function and needless; but at the same time, and by this very means, it is indicative of the ancestry of the organism in which it lingers." Its structure is that of the invertebrate eye, being marked by the peculiar feature in which this eye is different from, or opposite in the arrangement of the parts to, that of the vertebrate eye. Its presence suggests an ancient connection between the vertebrates and the tunicates, and their origin in one common stock; and supplies a new and most direct evidence in favor of the doctrine of the evolution of animal life.

Specimens of Paleolithic Art.—The river Tardoire in La Charente, France, is famous for the caves along its banks, out of which numerous evidences of occupation by prehistoric man have been collected from time to time. Among the objects which M. Eugène Paignon has recently found in one of the caves is a piece of reindeer-horn, perforated, of the form known as staff of command, which is covered with accurate and spirited engravings, and marked by work of such fineness that it can be seen best with a lens. On one of the faces of the staff is a representation of two seals, one of which is seen entire with its four limbs, the hinder limbs being faithfully rendered, and having five digits on each flap. The size of the tail is exaggerated. The body is covered with very evident hairs. The head is delicately executed, and the snout with its mustaches, the mouth, the eye, and the ear-orifice indicate genuine skill. The other seal is not entirely seen. It is larger and shows the marks of long hair on the neck. In front of the larger seal is a fish which may be a salmon or trout, for it is spotted like those fish, and its ventral fins are attached to the abdomen. Three plant-stems are seen near the fish. The opposite side of the horn is nearly covered with two long and slender animals, one