Nos. 1, 5, 9, 10 and 11 each have iv + 130 pages; nos. 2, 3, 4, 6, 7 and 8 each have iv + 162 pages; no. 12 has iv + 210 pages; no. 13 has iv + 216 pages; nos. 14 and 15 each have iv + 194 pages; no. 16 has iv + 234 pages; no. 17 has iv + 242 pages; no. 18 has iv + 238 pages; nos. 19 and 20 each have iv + 170 pages.