TAXOCRINIDAE 395 



I have, however, in recent years obtained a specimen from the Tournai limestone of 

 Belgium (PI. LIV, figs. 2a, b) which is a true Taxocrinus, and which according to the notions 

 of species prevailing in De Koninck's time would be referred to T. nobilis without the least 

 doubt, as in fact I did when it was first obtained. It now seems impossible to maintain the 

 identity of the two forms owing to the condition of the infrabasals in the type, which are 

 entirely within the ring of basals — the character on which I founded one of the families in 

 the other large division of the Flexibilia. I have not found another case so pronounced as 

 this among the Taxocrinidae, and therefore consider it a variation from the normal. With 

 a number of specimens we might find intermediate stages, but having only the one, so 

 thoroughly well preserved as Phillips's type, we can scarcely ignore this as a specific charac- 

 ter. I have therefore separated the Belgian form, chiefly on this character although there 

 are some others. 



Type. In the Gilbertson collection, British Museum of Natural Plistory, London. The 

 specimen is unique. 



Horizon and locality. Lower part of the Lower Carboniferous, or Mountain limestone, 

 equivalent to the Lower Burlington — Choteau — Knobstone of the United States ; Yorkshire, 

 England. 



Taxocrinus belgicus n. sp. 



Plate LIV, figs. 2a, b 

 A small species founded upon the specimen from the Belgian Lower Car- 

 boniferous mentioned under T. nobilis, which I have separated chiefly because it 

 has the infrabasals visible outside the column and upon the dorsal side of the 

 basals instead of within them. It also differs in the greater width of the pos- 

 terior basal, and more convex form of the calyx. The specimen is small, less 

 than half the size of the other — the figure being enlarged to two diameters. It 

 is notable for being the only example of true Taxocrinus thus far discovered in 

 the Belgian rocks. 



Type. Author's collection. 



Horizon and locality. Lower Carboniferous, Tournai stage ; Tournai, Belgium. 



Taxocrinus ramulosus (Hall) 

 Plate LIV, figs. 14-18 



Forbesiocrinus ramulosus Hall, Supplement Geology Iowa, i860, p. 67. 



Taxocrinus ramulosus, Wachsmuth and Springer, Revision Palaeocrinoidea, pt. I, 1879, p. 49. 



Forbesiocrinus subramalosus Shumard, Trans. Acad. Sci. St. Louis, II, 1866, p. 372. 



A medium-sized species. Crown low and broadly subturbinate, with 

 strongly prominent rays; almost as wide as high at the IIIBr; height to width 

 of average specimen, 1.2 to 1. Calyx to I Ax broadly pentagonal; height to 

 width, 1 to 2, with spread from base of 1 to 3.6. Rays relatively narrow below, 

 strongly convex and raised above the level of adjacent plates; arms strongly 

 divergent, not tapering rapidly until beyond the third bifurcation, where they 

 infold; divisions rather short. Sutures but little sinuous except in the higher 

 brachials. iBr numerous, areas broad and depressed below level of rays. 

 Surface smooth. Dimensions of crown in adult specimen : height, 25 mm. ; 



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