distal extremities of both jaws are without teeth; while there are ninety-two teeth in the hinder parts of the jaws, and these, as with other reptiles, were replaced by new ones as fast as they wore out. The skin was smooth, or covered only with epidermic scales. Some observers believe they have found in the foot-prints evidences that a slight web existed between the toes. M. Dollo has drawn a conjectural outline of the body of the iguanodon, which is represented in our large cut. Leaving out the long tail, its general shape is that of a duck. The sectional view, represented by X in the cut, indicates that the animal was relatively very narrow and sharp-keeled, like a clipper-ship. The tail, shaped like that of a crocodile, was probably a powerful swimming organ, like that of the duck. The neck was comparatively slender and capable of very free movements. The animal was an inhabitant of marshes—so far as is known, of fresh-water marshes only—and probably fed largely on ferns, abundance of which were found with the Bernissart specimens.
A multitude of other treasures besides the iguanodons were found at Bernissart, and are awaiting careful examination. Among them are crocodiles, in which two new genera have been defined; turtles, which have given one new genus; and "a vast quantity of fishes."
By SAMUEL YORKE AT LEE.
DETERIORATION of the eye has been, for many years, a topic of complaint—not only in the United States, but in Europe. In Germany, after a careful examination of the pupils in a public school, a surgeon has reported that the proportion of normal-sighted children is gradually less as the ages of the subjects advance: being thirty-six per cent in the primary classes to ninety per cent in the highest classes. Another German investigator reports that, from an examination embracing ten thousand children, it was found that the number of short-sighted in the elementary classes was from five to eleven per cent; in the higher school for girls, the proportion was from ten to twenty-four per cent; in the Realschulen, it was between twenty and forty per cent; in the gymnasia, between thirty and fifty per cent; and in the highest classes of all, between thirty-five and eighty-eight per cent. In an examination of six hundred students of theology at Tübingen, it was found that seventy-nine per cent suffered from myopia.
Similar examinations made in the schools of France and of England exhibit similar results, showing that the organ of sight grows weaker as the term of study grows longer. In the United States,