TAXOCRINOIDEA 4O9 



This extreme shortening of the crown is accompanied by a corresponding reduction 

 in the number of brachials ; 2 IIBr is the rule throughout upwards of 30 specimens, with 

 only two exceptions ; in the majority of cases the inner ramus of the IIIBr has only 2 

 (figs. 5, 6), never more than 3, and the outer not more than 4. No preceding species has 

 shown any such shortness in the arm divisions. There is also a tendency to reduction in 

 the number of IBr. I have found this in some rays of four specimens. The separation 

 of the radials by upward prolongation of basals, begun in T. sJiumardianus, is continued 

 to some extent, but quite irregularly, in this species. 



T. whMeldi is an exceedingly well-marked species, readily identified from fragments, 

 and it occurs over a wide field, having been collected in Illinois and in several counties in 

 Kentucky. Hall's type specimen is perfectly characteristic, and although not figured by 

 him he gave a good diagram from which it would be readily recognized ; nevertheless 

 several synonyms have sprung up which have to be suppressed, including one by himself. 

 Hall in the original description stated the horizon as Keokuk, and afterward in the Iowa 

 supplement corrected this to read, Warsaw. Neither is correct, as was pointed out in 

 1873 by Meek and Worthen, who figured and redescribed the type, and gave the locality 

 and horizon as opposite Kaskaskia, Randolph County, Illinois, in the Chester (Kaskaskia) 

 division of the Lower Carboniferous, on the authority of Professor Worthen, who col- 

 lected it. 1 Those authors (Geol. Illinois, vol. 5, p. 553) pointed out very clearly the differ- 

 ence between this species and Forbesiocrinus wortheni, and for the reasons there stated 

 referred it to Onychocrinus. While this reference under our present conception of the 

 latter genus cannot stand, the reasons given by Meek and Worthen are entirely valid to 

 establish its place under Taxocrinus, as distinguished from Forbesiocrinus as then under- 

 stood by American authors. 



Hall described his Forbesiocrinus cestriensis from a well-defined specimen of this 

 species from the Kaskaskia at Chester, Illinois, without any figure; this I have now 

 supplied for comparison from the type in the Worthen collection (fig. 11). Miller and 

 Gurley's figure of their Taxocrinus zvetherbyi needs only to be compared with that of the 

 type of T. whMeldi, figured long before their date by Meek and Worthen, and refigured 

 herein (PI. LX, fig. 1), to show the complete identity of the two. Nevertheless they 

 applied their stereotyped formula, and said : " the species is so different from all others 

 that no comparison with any of them is necessary to distinguish it." Wetherby's Forbesi- 

 ocrinus parvus is only a very young, and therefore more elongate, specimen of this species, 

 like figures 10a, b. His type specimen cannot be identified, but it is one of several small 

 specimens which cannot be distinguished from mine, and is from the same colony at 

 Sloan's Valley, Pulaski County, Kentucky, that produced numerous well-preserved speci- 

 mens such as are shown by my figures 2, 3, 4, 5, 8, 10. His figures, enlarged two diame- 

 ters, are undoubtedly incorrect in representing the interbrachials as continuing to an apex 

 between the arms — a structure which might easily be misunderstood in small, dark-colored 

 specimens like these. 



Types. Hall's original is in the Worthen collection, University of Illinois, also the 

 type of his F. cestriensis; that of Miller and Gurley's T. zvetherbyi, and specimens used by 

 Wetherby, are in the Walker Museum, University of Chicago ; the others studied and figured 

 herein are fn the author's collection. 



Horizon and locality. Close of Lower Carboniferous ; Okaw formation, upper part of 

 Kaskaskia Group. Randolph and Pope counties, Illinois, and Breckinridge, Grayson and 

 Pulaski counties, Kentucky. 



1 This is confirmed by my own collections from Randolph County. 



