280 ROBERT TRACY JACKSON ON ECHINI. 



*Archaeocidaris muensteriana (Koninck). 

 Plate 15, figs. 5a-5c. 



Cidaris muensterianus Koninck, 1842-'44, p. 35, Plate E, figs. 2a-2d. 



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



Echinocrinus munsterianus (?) M'Coy, 1844, p. 173, Plate 27, fig. 2 (name on legend of plate in pencil). 1 



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



Eocidaris munsterianus Desor, 1858, p. 156. 



Cidaris elegans M'Coy, 1862, [on legend of] Plate 27. 1 



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



Pholidocidarw gaudryi). 



Archaeocidaris munsteriana Loven, 1874, p. 43; Young, 1876, p. 230. 

 Archaeocidaris elegans Etheridge, 1888, p. 221. 

 Archaeoddaris munsterianus Etheridge, 1888, p. 221. 

 Eocidaris munsterianus Mem, 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. 

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

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

 Eocidaris forbesianus 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, 



1 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 as 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- 

 anus (see footnotes pp. 275, 277). 



