(1549) Proc. R. Soc. of Arts and Sciences of Mauritius, 1852, p. CXXXV.
      (1550) Gard. Chron., 1856 p. 379.
      (1551) QUATREFAGES, Maladies actuelles du Ver à Soie, 1859, pp. 12, 214.
      (1552) Gard. Chron., 1851, p. 595.
      (1553) Journal of Horticulture, 1862, p. 476.
      (1554) Gard. Chron., 1852, pp. 435, 691.
      (1555) BECHSTEIN, Naturgesch. Deutsch., 1801, vol. I, p. 310.
      (1556) PRICHARD, Phys. Hist. of Mankind, 1851, vol. I, p. 221.
      (1557) G. LEWIS, Journal of Residence in West Indies, in Home and Col. Library, p. 100.
      (1558) JOUATT, on the Pig, p. 24, ediz. Sidney. Ho riferito casi analoghi, relativi all'uomo, nella mia opera Descent of Man, ediz. 2a, p. 195.
      (1559) Journal of Horticulture, 1862, pp. 476, 498; 1865, p. 460. Relativamente alla viola del pensiero, vedi Gard. Chron., 1863, p, 628.
      (1560) Des Jacinthes, de leur Culture, 1768, p. 53; sul frumento, Gard. Chron., 1846, p. 653.
      (1561) W. B. TEGETMEIER, The Field, 25 febb. Relativamente ai polli neri, vedi la citazione di THOMPSON, in Nat. Hist. of Ireland, 1849, vol. I, p. 22.
      (1562) In Sachen Darwin's contra Wigand, 1874, p. 70.
      (1563) Bull. de la Soc. d'Acclimat., vol. VII, 1860, p. 359.
      (1564) Transact. Hort. Soc., vol. I, 2a ser., 1835, p. 275. Pei lamponi, vedi Gard. Chron., 1855, p. 154, e 1863, p. 265.
      (1565) Gard. Chron., 1843, p. 806.
      (1566) Ibid., 1850, p. 732.
      (1567) Ibid., 1860, p. 956.
      (1568) J. DE JONGHE, in Gard. Chron., 1860, p. 120.
      (1569) DOWNING, Fruit-trees of North. America, pp. 266, 501; relativamente al ciliegio, p. 198.
      (1570) Gard.