CATALOGUE OF NON-TRILOBITES. 363 



3. Sutured along the back. Notched in front. 



APTYCHOPSIS Barr., 1872; Syst. Sil. Boheme, vol. 1, suppl., p. 455. Angu- 

 lar notch. Middle and Upper Silurian (Murch.) 



PELTOCABIS Salt., 1863; Quart. Jour. Geol. Soc. London, vol. 19, p. 87. 

 Bounded notch. Lower Silurian (Murch.) 



PINNOCARIS Eth., 1878; Proc. Koyal Phys. Soc., Edinb., vol.4, p. 167. 

 Slightly notched. Lower Silurian (Murch.) 



II. Folded shield, bent along the back so as to form an overarching 



carapace, or a pair of attached valves. 



HYMENOCARIS Salt., 1852; Kep. 22d Meeting Brit. Adv. Sci., Trans. Sec., 

 p. 56. Smooth. Lingula-flags. Taconic. 



? CYTHEROPSIS TESTIS Barr, 1872. Not well known. (Lower Silurian 

 Murch.) 



PROTOCARIS Baily, 1872. Not well known. Uppermost Devonian or Low- 

 est Carboniferous. 



II. CARAPACE BIVALVED. 



SACOCARIS Salt., 1868; Proc. Geol. Polytech. Soc., vol. 4, p. 588. Strongly 

 emarginated behind. Lingula-flags. 



1. Pod-like. 



CARYOCARIS Salt., 1863; Quart. Jour. Geol. Soc. London, vol. 19, p. 139. 

 Pod-like; elongate narrow, smooth. Arenig and Lingula-flags. 



CERATIOCARIS McCoy, 1849; Annals Mag. Nat. Hist. London, 2d series, 



vol. 4, p. 412. 



Pod-like, subovate, suboblong, striate. Tremadoc and Devonian in 

 America. 



PHYSOCARIS Salt., 1860; Annals Mag. Nat. Hist. London, 3d series, vol. 5, 

 p. 159. Bound. Upper Silurian (Murch.) 



NOTHOZOE Barr., 1872; Syst. Sil. Boheme, vol. I, suppl., p. 530. Oval. 

 Lower Silurian (Murch.) 



CRYPTOZOE Pack., 1888. Proc. Acad. Nat. Sci. Phil., 1888, p. 381. Sub- 

 oblong. Carboniferous. 



XIPHOCARIS Jones and Woodward, 1886. Only telson known. Silurian. 



COLPOCARIS Meek, 1871; Proc. Acad. Nat. Sci. Phil., p. 334. Subovate; 

 strongly emarginate at one end. Carboniferous. 



2. Pod-like. Oculate. 



EMMELEZOE J. & W., 1886; Bep. 56th Meeting Brit.Adv. Sci., p. 232. 



Silurian. 



III. With swellings in the antero-dorsal region, one of whioh on each 



valve may be ocular. 

 ECHINOCARIS Whitf., 1880; Am. Jour. Sci., 3d series, vol. 19, p. 34. Leper- 



ditioid. Segments spinose. Devonian. 



ARISTOZOE Barr., 1872; Syst. Sil. Boheme, vol. 1, suppl., p. 474. Upper 



Silurian (Murch.) 

 OROZOEBarr., 1872; Syst. Sil. Boheme, vol. 1, suppl., p. 557. Upper 



Silurian (Murch.) 



