ARCHAEOCIDARIS. 279 



Portlock in his Plate 16, fig. 11 (here reproduced as Plate 14, fig. 16) that it is probably the 

 original of this figure. This plate is hexagonal, measures 11 mm. in width by 10 mm. in height; 

 has a prominent primary tubercle, basal terrace, and on the border a row of secondary tubercles 

 as figured by Portlock. This is the only published figure ascribed to the species vetusta. 



Julien's A. gruneri is in all probability simply based on small and probably young speci- 

 mens. It presents no specific differences. A . regimontana Parkinson is also doubtless a synonym. 



Lower Carboniferous, Fermanagh, North Ireland, Museum of Practical Geology, no. 7,659 

 (the holotype of Portlock's Cidaris benburbensis. See note above in regard to the locality 

 of this specimen) ; Benburb, Ireland, Trinity College, Dublin ; Knock Hill Quarry, Fife, Scot- 

 land, Museum of Practical Geology, nos. 16,316 to 16,319; Millstone Neuk, Dunbar, Scotland, 

 Museum of Practical Geology 25,507, 25,508; Fermanagh, Ireland, no. 16,321, and Clogher, 

 County Tyrone, Ireland, no. 7,768, Museum of Practical Geology; Hayfod-y-Calch, Corwen, 

 Wales, Sedgwick Museum, Cambridge; Yorkshire, Museum of Comparative Zoology Collec- 

 tion 3,062; near Glasgow, Museum of Comparative Zoology Collection; Bristol, British 

 Museum Collection 75,724; Bunderan; Ballantillich, Rahan's Bay, Ireland, and Derbyshire, 

 England, Sedgwick Museum, Cambridge, England; Craigenglen, Campsie, Scotland (Young); 

 Calderwood Limestone, in neighborhood of East Kilbride, Scotland (Neilson); Ardisiere, 

 France (Julien) ; Hunsrucken, Alsace, Germany (Tornquist) ; Culm, Konigsberg (Parkinson's 

 A. regimontana); Marbre Noir, Dinant, Belgium (Fraipont); Phillips (1836) gives as locali- 

 ties for his Cidaris vetusta, here considered a synonym, Ravenstonedale ; Whitewell, North- 

 umberland; Coalbrookdale and Florence Court. 



Archaeocidaris halliana (Geinitz). 

 Plate 15, figs. 4a-4c. 



Kuriilarix halliaiiii.s Geinitz, IStiG, p. til, Plate 5, figs, la, lb, 2a, 2b; Meek, 1872, p. 152, Plate 7, figs. 



9a-9(l; Klem, 1904, p. 68. 

 Eocidaris hallanm Miller, 1889, p. 242. 

 Archaeocidaris ludlianus Keyes, 1894, p. 129; 1895, p. 190. 

 (?) Eocidaris halliana Girty, 1903, p. .332. 

 Cidarotropus hallianm Lambert and Thiery, 1910, p. 125. 



Known only from isolated interambulacral plates and primary spines. Plates hexagonal, 

 wider than high, with basal terrace, as figured by Geinitz, large secondary tubercles in a single 

 row well in from the margin of the plate, and numerous minute granules on the marginal area. 

 Plates small, up to 3 mm., as given by Geinitz. Primary spine slender, terete, tapering from 

 the milled ring to the tip. Vertically finely striate, the elevated ridges being minutely and 

 regularly set with granules. Spines about 7 mm. long. 



Upper Coal Measures, Nebraska City, Nebraska; Kansas City, Missouri; (?) Leadville 

 district and Crested Butte district, Colorado. 



