We now come to the second o rder of the Trilobita, which Beecher (loc. cit.) calls the Opisthoparia. In common with the third order, the Proparia, compound paired eyes are usually present, and these are invariably situated on the free cheeks, which form part of the dorsal surface of the head-shield.
page 494 note 1 Hawle, and Corda, , Prodr. Mon. Boh. Trilob., 1847, p. 24, t. ii, f. 10.Google Scholar
page 494 note 2 C. Homfrayi (Salter) is stated to possess eyes, but from a careful examination of the type-specimen, which is much compressed and distorted, I have much doubt if they truly exist. In C. Lyelli (Hicks) the free cheeks are marginal, and the eyes which have been described appear to me to be merely the swollen ends of the ocular ridges on the fixed cheeks, and their visual function is doubtful. In cephalic structure this species agrees so closely with the Conocoryphe, sstr., of Corda, that after carefully examining the type-specimen, I am inclined to consider it a true member of the genus Conocoryphe and to be devoid of compound eyes.
page 494 note 3 Barrande, , Syst. Sil. Boh., vol. i, p. 415.Google Scholar
page 494 note 4 Bull. 30 U.S. Geol. Surv., 1886, p. 203;Google Scholar Amer. Journ. Sci., ser. III, vol. xxxiv (1887), p. 197;Google Scholar Fauna of the Olenellus Zone, 1890, p. 647;Google Scholar Ford, S. W., Amer. Journ. Sci., ser. III, vol. xix, p. 152.Google Scholar
page 494 note 5 Bibliogr. Pal. Crust. (California, 1893), p. 255.Google Scholar
page 494 note 6 Schlotheim, Nachträge z. Petrefakt., ii (Gotka, 1823), pl. xx, fig.1Google Scholar
page 494 note 7 Amer. Journ. Sci., vol. iii (1897), p. 188.Google Scholar
page 495 note 1 “Om Fauna i Kalken med Conocoryphe exsulans”: Sver. Geol. Undersokn., ser. C, No. 35 (1879).Google Scholar
page 495 note 2 Handb. v. Palaeont., vol. ii, p. 600.Google Scholar
page 495 note 3 Trans. Roy. Soc. Canada, vol. ii (1884), sect, iv, p. 102.Google Scholar
page 495 note 4 Amer. Journ. Sci., vol. iii (1897), p. 188.Google Scholar
page 495 note 5 Trans. Roy. Soc. Canada, vol. v (1887), p. 123.Google Scholar
page 495 note 6 de Paleout, Manuel. (traduit), 1886, p. 462.Google Scholar
page 495 note 7 Die Leitfossilien, 1896, pp. 21 and 360.Google Scholar
page 495 note 8 Bull. Soc. Geol. France, ser. in, vol. xxiii (1895), p 469, pl. iv, figs. 4, 5.Google Scholar
page 495 note 9 Pal. Scand., pp. 4, 5, pl. v.
page 495 note 10 Brit. Assoc. Report, 1865, p. 285;Google Scholar Quart. Journ. Geol. Soc., vol. xxviii (1872), p. 177.Google Scholar
page 496 note 1 Quart. Journ. Geol. Soc., vol. xxviii (1872), p. 178, pl. vi.Google Scholar
page 496 note 2 Barrande, Syst. Sil. Boh., vol. i, p. 915,Google Scholar pl. xxxiv, fig. 43. ibid., Suppl., vol. i, p. 19, pl. ii, figs. 4–6; pl. xiv, fig. 45.
page 496 note 3 Handb. Palæont., vol. ii, p. 625.Google Scholar
page 496 note 4 Geol. mag., 12. IV, Vol. V (1898), p. 206.Google Scholar
page 497 note 1 Q.J.G.S., vol. xx (1864), p. 337, pl. xiii, fig. 9; vol. xxviii (1872), p. 178, pl. Ti, figs. 8–10.Google Scholar
page 497 note 2 Barrande (Syst. Sil. Boh., Suppl., vol. i, p. 156) remarks that, judging from the figures, this species seems to be devoid of eyes.
page 497 note 3 Amer. Geol., vol. xvi (1895), pl. viii, fig. 6.Google Scholar
page 498 note 1 Atlantic Journ. and Friend of Knowledge, vol. i (1832), p. 71.Google Scholar
page 498 note 2 Amer. Journ. Sci., ser. i, vol. xxxv (1834), p. 336.Google Scholar
page 498 note 3 Hist. Nat. Crust., vol. iii (1840), p. 339.Google Scholar
page 498 note 4 Leonh. and Bronn, Jahrb. f. Min., 1843, p. 546.Google Scholar
page 498 note 5 Syst. Sil. Boh., vol. i, pp. 131, 145.Google Scholar
page 498 note 6 ibid., Suppl., vol. i, p. 161.
page 498 note 7 Jahrb. f. Min., 1845, p. 18.Google Scholar
page 498 note 8 Elemente d. Palæont., 1890, p. 490.Google Scholar
page 498 note 9 Trans. Roy. Soc. Canada, vol. ii (1884), sect. iv.Google Scholar
page 498 note 10 Das Antlitz der Erde, vol. ii, p. 274.Google Scholar
page 498 note 11 Erdgeschichte, vol. ii, p. 52.Google Scholar
page 498 note 12 Zittel, Handb. Palæont., vol. ii, p. 572.Google Scholar
page 499 note 1 Amer. Journ. Sci., ser. III, vol. xlvi (1893), p. 142.Google Scholar
page 499 note 2 Pal. Scand., p. 50, pl. xxvii, figs. 1 and 2.
page 499 note 3 Barraude, , Syst. Sil. Boh., vol. i, p. 890,Google Scholar pl. xviii; ibid., Suppl., vol. i, p. 155. Amelin, Pal. Seaiid., p. 91, pl. xli, figs. 21–3. Toraquist, Undersokn. Siljansoin. Trilobitf.: Sver. Geol. Undersokn., ser. C, No. 66 (1884), p. 89.
page 500 note 1 Holm, , “De Svensk. Art. Trilobitslae. Illsenus”: Bih.t. k.Vet. Akad. Handl., Bd. vii (1882), No. 3, p. 118, t. iv, f. 28; t. vi, f. 11.Google Scholar
page 500 note 2 Holm, ibid., p. 120, t. iv, f. 29.
page 500 note 3 Holm, , “Key. d. ostbalt. Silur. Trilob.,” Abtb. iii, Illæniden: 51em. Acad. Imp. Sci. St. Petersb., ser. VII, t. xxxiii (1886), No. 8, p. 162, t. xi, f. 11a–d.Google Scholar
page 500 note 4 Quart. Journ. Geol. Soc., vol. lii (1896), p. 413.Google Scholar
page 500 note 5 ibid., p. 593.
page 500 note 6 ibid., p. 414.
page 500 note 7 Svst. Sil. Boh., Suppl., vol. i, p. 68, pl. xiy, figs. 43, 44.Google Scholar
page 500 note 8 Bull. Soc. Geol. France, vol. xiii (1856), p. 532.Google Scholar Syst. Sil. Bob., Suppl., vol. i, p. 72, pl. y, figs. 28–37; pl. yi, figs. 1–4; pl. xiy, fig. 36.Google Scholar
page 500 note 9 Syst. Sil. Boh., Suppl., vol. i, p. 74, pl. iii, figs. 20–29.Google Scholar
page 500 note 10 Eiehter, Zeitsch. f. Deutsch. Geol. Gesell., vol. xv (1863), p. 659;Google Scholar ibid., vol. xvii (1865), p. 361.
page 500 note 11 Eiehter, , op. cit., vol. xv (1863), p. 670.Google Scholar
page 501 note 1 Hawle, and Corda, , Prodr. Mon. Boh. Trilob., 1847, p. 119.Google Scholar
page 501 note 2 Reynolds, S. H., Geol. Mao., 12. IV, Vol. I (1894), p. 108, Pl IV, Figs. 1, 5.CrossRefGoogle Scholar
page 501 note 3 Monogr. Sil. Foss. Girvan, fasc. i (1878), p. 115, pl. viii, fig. 8.Google Scholar
page 501 note 4 Salter and Blanford, “Palseont. of Niti,” 1865.
page 501 note 5 Hawle and Corda, Prodr. lion. Boh. Trilob., 1847, p. 128.
page 501 note 6 Geol. Mag., 12. IV, Vol. V (1898), p. 206.Google Scholar
page 502 note 1 Mon. Brit. Trilob., 1864, p. 16.Google Scholar
page 502 note 2 McCoy. Syn. Brit. Pal. Foss., 1851.Google Scholar
page 502 note 3 Barrande, Syst. Sil. Boh., Suppl., vol. i, p. 158.Google Scholar
page 502 note 4 Geol. Trans., 2nd ser., vol. vii (1846), p. 221, pl. xxv, fig. 14. Mon. Brit. Trilob., note on p. 60.Google Scholar
page 502 note 5 Proc. Brit. Assoc, 1852, p. 60.Google Scholar
page 502 note 6 Mem. Geol. Surv. Org. Rem., dec. vii, pl. ix.
page 502 note 7 Syn. Sil. Foss. Ireland, 1846, p. 43, pl. iv, fig. 1.Google Scholar
page 502 note 8 Reed, Quart. Journ Geol. Soc., vol. lii (1896), p. 410.Google Scholar
page 502 note 9 Pal. Scand., p. 58, pl. xxxiii, fig. S.
page 503 note 1 Undersokn. ofv. Siljans. Trilob. Svensk. Geol. Undersokn., ser. C, No. 66 (1884), p. 89.Google Scholar
page 503 note 2 Callaway, Quart. Journ. Geol. Soc., vol. xxx (1874), p. 196;Google Scholar ibid., vol. xxxiii (1877), p. 252.
page 503 note 3 Pal. Foss. Canada, vol. i (1862), p. 92.Google Scholar
page 503 note 4 Die Silur. Étagen 1 and 2, 1882, p. 125.Google Scholar
page 504 note 1 Barrande, Syst. Sil. Boh., vol. i, p. 131;Google Scholar ibid., Suppl., vol. i, pp. 155–162.
page 505 note 1 Amer. Journ. Sci., vol. iii (1897), p. 182.Google Scholar