248 bulletin: museum of comparative zoology. 



IsoTELUS GiGAS Dekay. 



Plate 1, fig. 1, 2; Plate 2, fig. 2-5; Plate 3, fig. 3. 



Isotelus gigas Dekay, Ann. Lyceum nat. hist. N. Y., 1824, 1, p. 176, pi. 12, 

 fig. 1. Green, Monthly Amer. journ. geol., 1832, 2, p. 560; Monog. 

 trilobites N. Amer., 1832, p. 68, casts 21, 22. Milne Edwards, Crustac^s, 

 1840, 3, p. 298. Vanuxem, Rept. Third geol. dist. N. Y., 1842, p. 46, 

 fig. 1. Emmons, Rept. Geol. dist. N. Y., 1842, p. 389, fig. 1. Hall, 

 Pal. N. Y., 1847, 1, p. 231, pis. 60-63. Emmons, Amer. geol., 1855, 1, 

 pt. 2, p. 215, pi. 16, fig. 12. W. B. Rogers, Geol. Penn., 1858, 2, p. 819, 

 fig. 610. Miller, Cincinnati quart, journ. sci., 1874, 1, p. 138. Clarke, 

 Pal. Minn., 1897, 3, pt. 2, p. 701 ipartim) fig. without number. Weller, 

 Pal. N. J., 1902, 3, p. 192, pi. 14, fig. 6, 7 (non 5). Raymond and Narra- 

 way, Ann. Carnegie mus., 1910, 7, p. 53, pi. 15, fig. 1, 2. Raymond, 

 Trans. Roy. soc. Canada, 1912, .ser. 3, 5, sect. 4, pi. 2, figs. 7, 8; pi. 3, 

 fig. 6. 



Isotelus planus Dekay, Ann. Lyceum nat. hist. N. Y., 1824, 1, p. 178, pi. 13, 

 fig. 7. Green, Monthly Amer. journ. geol., 1832, 2, p. 560; Monog. 

 trilobites N. Amer., 1832, p. 68, cast 23. 



Isotelus Cyclops Green, Monthly Amer. journ. geol., 1832, 2, p. 560, pi., fig. 7; 

 Monog. trilobites N. Amer., 1832, p. 69, cast. 24. 



Isotelus megalops Green, Monog. trilobites N. Amer., 1832, p. 70, cast 25. 



Isotelus stegops Green, Monog. trilobites N. Amer., 1832, p. 71, casts 26, 27. 



Isotelus jacobus Clarke, Pal. Minn., 1897, 3, pt. 2, p. 706, footnote. 



? Asaphus platycephalus Stokes, Trans. Geol. soc. London, 1823, ser. 2, 1, 

 pi. 27, no description. Buckland, Geol. and niin., 1837, 2, p. 73, pi. 45, 

 fig. 12; Ibidem, 1867, pi. 63. 



Asaphus platycephalus Bronn, Lethaea geogn., 1835, 1, p. 115, pi. 9, fig. 8; 

 Ibidem, 1851-1856, 1, p. 632, pi. 9, fig. 8; pi. 9, fig. 5. Burmeister, Die 

 org. der trilobiten, 1843, p. 127, pi. 2, fig. 12; Ray society edition, 1846, 

 p. 110, pi. 2, fig. 12. Walcott, Bull. M. C. Z., 1881, 8, p. 198, pi. 2, fig. 9. 



Asaphus gigas Dalman, K. Svensk. vet. akad. Handl., 1826, p. 276; Om Palaea- 

 derna, 1827, p. 91; Ueber die Palaeaden, 1828, p. 70. 



Asaphus planus Dalman, K. Svensk. vet. akad. Handl., 1826, p. 276; Om 

 Palaeaderna, 1827, p. 91; Ueber die Palaeaden. 1828, p. 70. 



Asaphus megistos Bilhngs, Geol. Canada, 1863, p. 184, fig. 182. 



Brongniartia isotelea Eaton, Geol. text book, 1832, p. 33, pi. 2, fig. 12. 

 The following have been erroneously referred to this species: — 



Isotelus gigas Portlock, Geol. rept. Londonderry, 1843, p. 295, pi. 7, fig. 1; 

 pi. 8, fig. 1. McCoy, Synopsis Silurian foss. Ireland, 1846, p. 53. Brog- 

 ger, Bihang K. Svensk. vet. akad. Handl., 1886, 11, p. 31, pi. 1, fig. 18 

 (= Isotelus platyrhachis Steinhart, teste Schmidt). Clarke, partim, Pal. 

 Minn. 3, 1897, pt. 2, p. 703, fig. 5 (= Isotelus iowensis). Weller, Pal. 



