182 BRITISH PALAEOZOIC PIIYLLOCARIDA. 



species, named after Dr. John Youug, F.G.S., Under-keeper of the Hunterian 

 Museum, University, Glasgow, wbo possesses the specimen. 



From Lower Carboniferous series. Li the Upper Limestone group, at Robroy- 

 ston,' Lanarkshire ; with black, non-calcareous shale, about 300 fathoms below 

 the Ell Coal. 



At Robroyston, about three miles north-east of Glasgow; the strata are under 

 the Upper Limestone, in the Possil Ironstone series. 



Calyptocaris,^ gen. nov. 



This phyllopod differs from DifJii/rocaris in having had a bivalved shell capable 

 of being closed. Its costulate ornament approximates to that of I). Belli. 



1. Calyi'jocakis siKiATA (H. Woodu-tinl), lS/1. Plate XVIII, fig. 7. 



DiTHTEOCAUis sTiiiATUs, H. Wooil iciiTtI, 1871. Eeport Brit. Assoc, for 1870, 



Sections, p. 91. 

 ? — STEIATA, Woodwnnl and Etheridge, 1873. Memoir Geol. Surv. 



Scotlaud, E.xplau. Sheet 23, Appendix, pp. 49, 57, 

 100; Geol. Mag., 1874, p. 109, pi. v, fig. G; Eeport 

 Brit. Assoc, for 1873, Sections, p. 92. 



— — Armstroncj and others, 1876. Catal. "W.-Scotl. Fossils, 



p. 29. 



— — Sigsl'i/, 1878 Tliesaur. Uev.-Carb., p. 249. 



— — £., W.,a!u/ J.,18H7. Eep. Brit. Assoc, for 1886, p. 65. 



— — W. W. and J., 1899. Geol. Mag., dec. 4, vol. vi, p. 28. 



— — — 1899. Eep. Brit. Assoc, for 1898, p. 520. 

 Calaptccaeis sTJiiATA, — 1899. Geol. Mag., dec. 4, vol. vi, p. 29. 



— — — 1899. Eep. Brit. Assoc, for 1898, p. 521. 



Size. — Length of valve probably 30 mm. ; breadth of valve is 15 mm. 



Specific Characters. — This imperfect bivalved test has been filled with matrix, 

 and the hinder moiety has been broken away. The remaining front part repre- 

 sents the exterior of the left valve ; the hinder moiety shows the inside of the 

 right valve as far as it reaches ; the posterior border of both valves is absent. 

 The front end of the left valve is obliquel}' truncate, with rounded corners ; and 

 it formed apparently one side of an open angle between the antero-dorsal regions 

 of the two valves when they were perfect and open. The surface bears eight or 

 nine longitudinal riblets ; those on the ventral region are parallel to the curved 



' A description of tliia locality is given at p. 88 of the ' Catalogue Western-Scottish Fossils,' 

 1876. 1). tenuiitriata, at pp. 45 and 89, probably refers to this fossil specimen. 

 ■^ K(iAi/7iT0), 1 close or hide ; and xapi's, a shrimp. 



