PLATYCRINID^. PLATYCRINITES. 



the imdeniable fact that in all the more perfect specimens no division whatever is 

 observable. 



As it is more difficidt to erachcate an error of long standing, tlian it is to establish a 

 new fact, we have considered it necessary to offer this rather chffnse explanation. 



1. Species. Platycrinites l,evis. (Miller.) 



Definition. — Dorso-central plate (pelvis) entire and pentagonal, with a central jier- 

 foration commnnicating with the columnar canal. Perisomic plates five, broad, smooth, 

 and somewhat orbicidar on their lower edges, by wluch they fit into the undulations in 

 the rim of the dorso-central plate. Towards their tnincated summits, and about equi- 

 distant fi'om the sides, are the horse-shoe shaped excavations for the attachment of the 

 rays. The lower surfaces of these excavations are sloped at a high angle, to correspond 

 TOth the attaching surfaces in the rays. Plates covering the abdominal cavity smooth. 

 Proboscis, or oral tube, central and greatly elongated. Main rays five, subcU^vided 

 twice, making twenty lesser rays, all dorsally roimded and closely tentaculated to their 

 points. Column circidar at and near the attachment to the dorso-central plate, but 

 elliptical as it recedes from it, witli circidar auxiliary side arms. 



Synonymes and References. 



Parkinson's Org. Rem. Vol. II. PI. U.fig. 12. 

 Cumberland, Trans. Geol. Soc. Vol. V. PL b.fig. 8. 

 Platycrinites lse\is. — MiUer, Nat. Hist. Crinoidea, PI. I. mid II. jmge 7-1. 



— Scliloth. Nacht. 11 tab. 25. fg. 4. a /;. 



— Bronn. Pfanzenth. tab. 'i.fig. 9. 

 — Goldfuss, Petrefacta Germania, tab. L VIII. Jig. 2. 

 — Blainville, Man. D'Actinologie, page 262. Paris ed. 1834:. 

 — Cu\ier, Le R^gne Animal, Zoophytes, tab. "^-fig. 3. Paris ed. 



1837. 



Localities and Formation. 



Carboniferous limestone, Lancashire; Mendip Hills; Clevedon Bay; Frome; the 

 Black Rock, on the Avon side, near Bristol ; Bleadon, near UphiU, Somersetshii-e ; 

 VaUey of the Maine, Kerry; ^dcinity of Dublm; Cork; Kildare; Hook Point, Wex- 

 ford; Granagh Ferry, Kilkenny; Lough Macnean'? &c. 



