72 CALIFORNIA ACADEMY OF SCIENCES. 



Ellipsocephalus Jioffi Schloth. Asaphus extenuatus Wahl. Acidaspis verneuilli 

 Barr., A. leonhardi Barr. Dalmanites socialis Barr. Eye of Bronteti* 

 brongniarti. Illcenus tauricornis, etc. 



Giebel (C.) Die silurische Fauna des Unterharzes. 



In Abhandl. Nat. Vereins Sachsen u. Thiiringeu, vol. 1, 1858, p. 1, 7 pis. 



Harpes bischofi A. Roem. Proetus pictus n. sp. Cyphaspis hydrocephala 

 Romer. Phacops angustic.eps n. sp., P. ? sternbergi n. sp. Dalmanites 

 tuberculatus n. sp. Lichas sexlobatus Romer. Acidaspis selcana Romer, 

 A. hercynice n. sp. Bronteus bishofi 11. sp. 



Goldfuss (A.) Observation sur la place qu'occupent 

 les Trilobites dans le rgne animal. 



In Annales Sci. Nat. Paris, vol. 15, 1828, p. 82, pi. 2. 

 Asaphus. Calymene. 



- Catalogue des Trilobites. 



In Handbuch der Geognosie von de la Beche, 1832. 



This list was copied by Dr. Jacob Green in his "Monograph of the 

 Trilobites of North America," p. 20. 



- Beitrage zur Familie der fossilen Crustaceen. 



In Nova Acta Physico Med., vol. 19, 1839, Breslau, p. 353, pi. 33. 



Harpes n. g. Arges n. g. Bostrichopus u. g., B. antiquus n. sp. Arges 

 armatus n. sp. Harpes macrocephalus n. sp. Brontes flabeU'tfer n. sp. II- 

 Ifenus ? triacanthus n. sp. 



Systematische Uebersicht des Trilobiten und 



Beschreibung eniger neuen Arten. 



In Neues Jahrbuch fiir Mineral., 1843, p. 537, pis. 4-6. 

 New genera Anthes, Gerastos and Symphysurus. 



The author classifies 204 species under 31 genera principally on the 

 characteristics of the eyes as follows: 



I. Without eyes, a without segments. 1, Agnostus Brong. b with 

 segments. (a) segments of the pygidiuni effaced. 2, Ampyx. 3, Crypto- 

 lithus. 4, Arges. 5, Olenus. (b) segments of the pygidium distinct. 6, 

 Zethus. 7, Otarion. 



II. Eyes smooth or finely reticulated. A Thorax and pygidium indis- 

 tinctly separated, (a) The last segment without appendages. 8, Para- 

 doxides. 9, Amphion. 10, Harpes. (b) The last segment with append- 

 ages. 11, Bronteus. 12, Ellipsocephalus. 13, Ceraurus. 



B Pygidium clypiform, axis and sides not segmented, a without dorsal 

 grooves. The axis and sides indistinct. 14, Nileus. 15, Bumastus. b 

 Dorsal grooves faint. Grooves of the sides invisible on the pygidium. 

 16, Dipleura. c Dorsal grooves prolonged even to the pygidium. 17, 

 Symphysurus. 18, Illoeuus. 19, Isotelus. Pygidium clypiform, axis seg- 



