süBCLASs I TRILOBITA 693 



cephalon, thorax and ahdomen distind. Cephalon covered with a shield composed of 

 a primitivehj pentamerous middle piece, the cranidium, and two side pieces, or free 



Mineral. Gesellsch. St. Petersburg, 1857-58. — Salter, J. W., A Monograph of British Trilobites. 

 Palaeontographical Society, 1864. — Idem and Woodward, H., Ibid., 1867-84. — Schmidt, F., 

 Revision der ostbaltischen silurischen Trilobiten. Mem. Acad. Inip. St. Petersbourg, 1882-1907, 

 ser. 7, vol. XXX., and ser. 8, vol. xii, — Brögger, W. C, Die silurischen Etagen 2 und 3 in Kristiana- 

 gebiet und auf Eker, 1882. — Holm, O., De Svenske Arterna af Trilobitslägtet Illaenus. Bihang 

 Svensk. Vetensk. Akad. Handl., 1882, vol. vii., no. 3. — Matthew, G. F., Illustrations of the 

 Fauna of the St. John's Group, 1882-93. — Woodioard, H., Monograph of the British Carboniferous 

 Trilobites. Palaeontogr. Soc, 1883. — Hall, J., and Clarke, J. M., Palaeontology of New York, 

 1888, vol. vii. — Walcott, C. D., The Fauna of the Lower Cambrian or Olenellus Zone. lOth Ann. 

 Rept. U.S. Geol. Surv., 1890. — Jaekel, 0., Über die Organisation der Trilobiten. Zeitschr. Deutsch. 

 Geol. Ges., 1901, vol. liii. — Lake, P., Monograph of British Carabrian Trilobites. Palaeontogr. 

 Soc, 1906-1913. — Lorenz, T., Beiträge zur Geologie und Paläontologie von Ostasien, der Provinz 

 Schantung, etc. Zeitschr. Deutsch. Geol. Ges., 1906, vol. Iviii. — Monk, H., Beiträge zur Geologie 

 von Schantimg. Jahrb. Preuss. Geol. Landesanst. Bergakad., 1905, vol. xxiii. — Moberg, J. C, and 

 Segerberg, C. 0., Bidrag tili Kannedomen om Ceratopygeregionen med Särskild Hänsyn tili dess 

 Utveckling i Fogelsangstrakten. Acta Universitatis Lundensis, 1906. — Olin, E., Om de Chasmops- 

 kalken och Trinucleusskiffern Motsvarande Bildningarne i Skäne. Acta Universitatis Lundensis, 

 1906. — Raymond, P. E., The Trilobites of the Chazy Limestone. Annais Carnegie Mus., 1905, 

 1910, vols. iii., vii. — Idem, and Narraway, J. E., Notes on Ordovician Trilobites. Ibid., 1906, 

 1910, vols. iv. , vii. — Reed, F.R. C, Lower Palaeozoic Trilobites of the Girvan District. Palaeontogr. 

 Soc, 1903-1906. — Idem, The Lower Palaeozoic Fossils of the Northern Shan States. Burma. 

 Palaeont. Indica, 1906. — Idem, The Cambrian Fossils of Spiti. Palaeont. Indica, 1910. — Walcott, 

 G. D., The Cambrian Faunas of China. Proc. U.S. Nat. Mus., 1906, and Smithson. Mise Coli., 

 vol. xxix., 1911. — Idem, Cambrian Trilobites. Geology and Paleontology. Smithson. Mise Coli., 

 1908-11, vols. liii., iv. — Weller, S., Paleontology of the Niagaran Limestone in the Chicago Area. 

 Bull. Chicago Acad. Sei., 1907, no. 4. 



B. Structure and Appendages : Burmeister, II., vide supra, 1843. — Billings, E., Notes on 

 some Specimens of Lower Silurian Trilobites. Quar. Journ. Geol. Soc, 1870, vol. xxvi. — Woodxoard, 

 H., Note on the Palpus and other Appendages of Asaphus from the Trenton Limestone in the 

 British Museum. Quar. Journ. Geol. Soc, 1870, vol. xxvi. — Walcott, G. D., Preliminary Notice 

 of the Discovery of the Natatory and Branchial Appendages of Trilobites. 28th Rept. N.Y. State 

 Mus. Nat. Hist., 1875. — The Trilobite ; New and Old Evidence relatiug to its Organization. Bull. 

 Mus. Comp. Zoology, 1881, vol. viii. — Novdk, 0., Studien an Hypostomen böhmischen Trilobiten. 

 Sitzungsber. Böhm. Ges. Wiss., Jahrg. 1879, 1886. — Glarke, J.M., The Structure and Development 

 of the Visual Area in the Trilobite Phacops rana Green. Journ. Morph ology, 1888, vol. ii. — 

 Matthew, W. D., On Autennae and other Appendages of Triarthrus beckii. Amer. Journ. Sei., 1893, 

 (3), vol. xlvi. — Beecher, G. E., On the Thoracic Legs of Triarthrus, ibid., 1893. — On the Mode 

 of Occurrence, and the Structure and Development of Triarthrus becki. American Geologist, 1894, 

 vol. xiii. — The Appendages of the Pygidium of Triarthrus. Amer. Journ. Sei. 1894 (3), vol. xlvii. 

 — Further Observation« on the Ventral Structure of Triarthrus. Amer. Geologist, 1895, vol. xv. — 

 The Morphology of Triarthrus. Amer. Journ. Sei., 1896 (4), vol. i. — Structure and Appendages 

 of Trinucleus, ibid., 1895. — Studies in Evolution, New York, 1901. — The ventral integument of 

 Tribolites, Amer. Journ. Sei., 1902 (4), vol. xiii. — Lindström, G. Researches on the Visual Organs 

 of Trilobites. Svensk. Vet. Akad. Handl., 1902, vol. xxxiv. 



C. Ontogeny : Barrande, J., vide supra, 1852. — Beecher, G. E., The Larval Stages of Trilobites. 

 Amer. Geologist, 1895, vol. xvi. — MattJiew, G. F., Sur le developpement des premiers Trilobites. 

 Ann. Soc. Roy. Mal. de Belgique, 1889, vol. xxiii. — vide ante, 1882-93. 



D. Systematic Position : Zittel, K. A., Handbuch der Palaeontologie, 1881-85, vol. iii. — Grundzüge 

 der Paläontologie, 1895. — Lang, A., Text-book of Comparative Anatomy. English Translation by 

 H. M. and M. Bernard. 1891. — Kingsley, J. S., Tlie Classification of the Arthropoda, Amer. 

 Nat., 1894, vol. xxviii. — Bernard, H. M., The Systematic Position of the Trilobites. Quar. Journ. 

 Geol. Soc, 1894-95, vols. 1., li. — The Zoological Position of the Trilobites. Science Progress, 

 1895, vol. iv. — Woodioard, H., Some Points in the Life-History of the Crustacea in Early Palaeozoic 

 Times. Quar. Journ. Geol. Soc, 1895, vol. li. — Haeckel, E., Systematische Phylogenie der 

 wirbellosen Tiere (Invertebrata), 1896. — Beecher, G. E., Outline of a Natural Classification of the 

 Trilobites. Amer. Journ. Sei., 1897 (4), vol. iii. 



E. Classification: Barrande, J., vide suj)ra, 1852. — Beecher, G. E., ante, 1897. — Brongniart, 

 A., ante, 1822. — Biirmeister, H., ante, 1843. — Gmda, A. J. G., and Hawle, J., ante, 1847. — 

 Haeckel, E., ante, 1896. — IJalman, J. W., Oiu Palaeaderna eller de sä kailade Trilobiterna 

 Stockholm, 1826. — Milne Edwards, IL, Histoire naturelle des Crustact's, 1834-40. — Quenstedt, 

 F. A., Beiträge zur Kenntniss der Trilobiten. Wiegmann's Archiv für Naturgesch., 1837, vol. iii. 

 — Emmrich, H. F., De Trilobitis. Dissertation, 1839. — Zur Naturgeschichte der Trilobiten, 1844. — 



