GEOLOGICAL AND GEOGRAPHICAL DISTRIBUTION. 143 



Codasteridse (continued). 



*L. Orophocrinua gracilis, Meek 8; Worthen, sp. 



*h. Orophocrinua stelliformis, Owen ty Shumard, sp. 



*L. Orophocrinua BtelliformiSj var. campanulatus, Hambach, var. 



( renera undetermined : — 



[Pentremites] decussatus, Shumard. 

 [Pentremites] Sirius, White. 

 *L.[Granatocrinus] Shumardi, Meek fy Worthen. 



Genus and horizon undetermined : — 

 [Granatocriuus] lotoblastus', White. 



3. Keokuk Group. 



Troostoblastidae. 



Metablastus bipyramidalis, Hall, sp. 

 *Metablastus Wortheni, Hull, sp. 

 *Tricoelocrinus Woodniaui, Meek § Worthen. 



Nucleoblastidre. 



Schizohlastus ? granulosus, Meek ix Worthen, sp. 



Genus undetermined : — 



[Coclastcr] gratiosus, Miller. 



4. St. Louis Group, including the Warsaw Limestone. 



Pentremitidse. 



Pentremites Bradleyi, Meek, MS. 

 *Pentremites conoideus, Hall. 

 *Pentrernites conoideus, var. Koninckanus, Hall, var. 



Pentremites subconoideus, Meek, MS. 

 *Mesoblastus glaber, Meek t y Worthen, sp. 



Troostoblastidae. 



Troostocrinus ? Grosvenori", Shumard, sp. 

 *Metablastus Varsouviensis, Meek fy Worthen, sp. 

 *Metablastus WachsmuthL Gurley, sp. 



1 This species has been found at two localities in the West, where the subdivisions of the Mississippi 

 Valley series cannot be clearly made out, and its precise horizon is therefore more or less uncertain. It 

 prob tbly belongs to the Nucleoblastidse, and we have therefore associated it with the Burlington Limestone, 

 in which this family is abundantly represented. 



-' According to Shumard, this fossil was found in the Archimedes Limestone at Spergen Hill, Indiana. 

 We do not know whether this is the bed that is generally known as the Oolitic or the Warsaw Limestone ; 

 but it does not appear to he the same as the " Upper Archimedes " or Kaskaskia Limestone of the Chesti i 

 Group. 



