volume xxiii, pp. 314, 315.--ED.

[48] See Plate 51, in the accompanying atlas, our volume xxv.--ED.

[49] See Plate 46, in the accompanying atlas, our volume xxv.--ED.

[50] See Plate 55, in the accompanying atlas, our volume xxv.--ED.

[51] See Plate 54, figure 1, in the accompanying atlas, our volume xxv.--ED.

[52] See our volume xiv, pp. 282, 283.--ED.