280 ROBERT TRACY JACKSON ON ECHINI. 



*Archaeocidaris muensteriana (Koninck). 



Plate 15, figs. 5a-5c. 



Cidari^ muensterianus Koninck, lS42-'44, p. 35, Plate E, figs. 2a-2(l. 



Cidarites munsterianm Koninck, 1842-44, [description of] Plate E. 



Echinocrimis mumterianm (?) M'Coy, 1844, p. 173, Plate 27, fig. 2 (name on legend of plate in pencil).' 



Cidaris munsferiana L. Agassiz and Desor, 1846-'47, p. 367. 



Eocidaris munstcrianus Desor, 1858, p. 156. 



Cidaris elegans M'Coy, 1862, [on legend of] Plate 27.' 



Lepidocentrus munsierianus Koninck, 1869, p. .546; 1870, p. 260; (non .lulien, 1874, p. 76, for which see 



Pholidocidaris gatidry i ) . 

 Archacocidaris yniinsirriana Loven, 1874, p. 43; Young, 1876, p. 2.30. 

 Archacocidaris cicgans Etheridge, 1888, p. 221. 

 Archaeoddaris munsterianus Etheridge, 1888, p. 221. 

 Eocidaris milnsterianus Klem, 1904, p. 69. 

 Eocidaris munsteri Lambert and Thiery, 1910, p. 126. 



Known only from primary spines and incomplete interambulacral plates. Interambulacral 

 plates of doubtful outline, probably hexagonal, primary tubercle with large scrobicular area; 

 a basal terrace is not figured, but it is quite likely worn off. Primary spines spindle-shaped, 

 with numerous vertical denticulate ribs, arranged regularly in parallel series. 



Lower Carboniferous, Vise, Belgium; Ireland; Beith district, Ayrshire in Scotland (Young) ; 

 Vise, and Tournai, Belgium, British Museum Collection 32,846 and 56,991. 



Archaeocidaris forbesiana (Koninck). 



Plate 15, figs. 6a-6e. 



Cidaris forbesiana Koninck, 1863, p. 574, Plate 4, figs. 1, 2; 1863a, p. 4, Plate 4, figs. l-2a. 

 Eocidaris forbesiana Waagen, 1879-'87, p. 819, Plate 95, figs. 5-16. 

 Permocidaris forbesiana Lambert, 1899a, pp. 39, 47. 

 Eocidaris forbcsianus Klem, 1904, p. 67. 

 Permocidaris forbesi Lambert and Thiery, 1910, p. 127. 



This species is known from isolated interambulacral plates and spines. The plates are most 

 imperfectly known, and the figures given by Waagen seem to be of quite impossible shapes 

 as regards outline, also the primary tubercle is so peculiar that it differs from that of any known 

 type. With the meager knowledge and doubtful character of the material, it seems to me 

 best to place it in Archaeocidaris rather than make it the basis of a distinct generic type, as 

 does Lambert. The primary spines on which the species was based by de Koninck, are large, 



' In a copy of M'Coy's Carboniferous Fossils of Ireland of the 1862 edition, seen at the Jermyn St. Museum, the name 

 Cidaris elegans is printed on the plate a-s stated. In two copies of the 1844 edition, one at the British Museum, and one at 

 the Museum of Comparative Zoology, the name on the plate is erased and changed in pencil to read Echinocrinus munster- 

 amis (see footnotes pp. 275, 277). 



