Poly. 



732 



Polypi. Polyps. An extensive class of Palaeozoic fossils, 

 divided into two orders : the Zoantharia, and the Alcyonaria. 

 The first includes the seven families of Astrceidce^ Cyathophyl- 

 hdcB^i Cyathaxonidce^ FavositidcB^ Halysitidce, Milleporid^^-) 

 and Poritidoe* The second includes the three families of Al- 

 cyonidm^ Tubiporidce^ and Oraptolitidce. (S. A. Miller's cat. 

 1877, 1883.) — Many of the genera and species are characteris- 

 tic of formations ; for example, the Lithostrotion^ which, in 

 Warren, Pa., and along the Allegheny mountain southward 

 into Alabama, and westward into Kentucky, marks the Mauoh 

 Chunk red shale horizon {XI) between the Subcarboniferous 

 PoGono conglomerate (X) beneath it, and the Carboniferous 

 Pottsville conglomerate {XII) over it. See Randall's section 

 in Oarll's Report I, page 53, etc., etc. 



Polypora ? Olaypole's specimen 5-1, from Barnett's 



Mill, Perry Co., Pa. in Hamilton upper shale, VIII c. 



Polyrhizodus ampins. St. John & Worthen, Geo. Sur. 



^r '--->^^_ '^^- Ill.,VoL6,1875, 



glllfPl^^^^^ page 387, plate 



13. figs IZa 6, 

 perfect fish- 

 tooth, concave 



SVi. <«' *;;'f - - Geol.Sll./S-rs: Pi. Ig. ^^d convex sur- 



faces, from Alton, 111. Not rare in the 8t, Louis limestone 

 suhbarioniferous.) XL 



Polyrhizodus carbonarius. St. John & Worthen, Geo. 



XV. 





(:5b. 



: 5 * . 







Geol. /^ 



9U. M 



WTx 







Vy 



7 J J y0* 



-•' n 



A ■: ^ 



Sur. 111., Vol. 6, 1875, page 389, plate 10a, figs. 24a, to 25e, and 

 plate 13, fig. 10a, Appearance of the original example, con- 



