The “Apollo” statues,[821] because of differences in facial expression, have been conveniently divided into two groups: those represented by the examples from Thera, Melos, Volomandra, Tenea, etc., sometimes named the “grinning” group, because the corners of the mouth are turned upwards into the so-called “archaic smile,” and those represented by the examples from Orchomenos, the precinct of Mount Ptoion, and elsewhere, named the “stolid” group, because in them the mouth forms a straight line.[822] There are, however, essential differences between the statues of each group. Thus, while some of both groups—_e. g._, the examples from Melos, Volomandra, and Orchomenos—have square shoulders, most of the others have sloping ones. The type gradually improved, as in each successive attempt the sculptor overcame difficulties, until finally revolutionary changes had taken place in the original form. This improvement is seen in the treatment of the hair, in the modeling of the face and body, and in the proportions of the statues. In a head of a statue from Mount Ptoion[823]—which is broken off at the neck—we seem to see the sculptor in wood making his first attempt in stone. In the archaic example from Thera[824] (Fig. 9) the arms hang straight down close to the sides, as in the statue of Arrhachion, being detached only slightly from the body at the elbows, showing that the artist was afraid that they might break off. In other examples, as in the one from Orchomenos[825] (Fig. 10) and one from Mount Ptoion[826] (Fig. 11), the space between the arms and the body has become larger, while in the example from Melos[827] (Fig. 12) only the hands are glued to the thighs. In the “Apollo” found at Tenea in 1846, and now in Munich[828] (Pl. 8A), the arms are free, but the hands are held fast to the body by the retention of small marble bridges between them and the thighs. The final step has been taken in two examples from Mount Ptoion (Fig. 13), in which the arms from the shoulders down are free from the bodies.[829] The bridges shown on the photograph in the figure to the left, which connect the forearms with the thighs, are of plaster, being added at the time the statue was set up in Athens.[830] The figure to the right is smaller and clearly discloses Aeginetan influence. The audacity of the sculptor in entirely freeing the arms in both examples was rewarded by the arms being broken off. Similarly, in the _Strangford Apollo_ of the British Museum (Fig. 14),[831] the arms, which hung loose from the shoulders, are broken away. The larger statue from Mount Ptoion just mentioned also has the arms slightly crooked at the elbows, the forearms being extended at an oblique angle to the body. This represents an intermediate stage between the earlier “Apollos,” in which the arms adhered vertically to the sides of the body (as _e. g._, in the ones from Orchomenos, Thera, Melos, and Tenea), and the later ones, in which the arms were bent, the forearms