254 W. IT. SHERZEK — THE GENTS CHONOPHYLLVM. 



Introductory. 



This paper will aim to do for one genus of Paleozoic corals what is 

 much needed for many others: it will attempt to give definiteness to the 

 set of characters by which the genus may be recognized, will examine 

 the various species assigned to it with reference to these characters, and 

 will indicate the special points of structure by which it may be distin- 

 guished from its nearest relatives. 



The work was begun upon the suggestion and under the direction of 

 the late lamented Dr. Alexander Winchell, with the freedom of his 

 valuable paleontological library. 



Historical and Descriptive. 



In the first volume of his great work, published in 1826, the learned 

 ( roldfuss described and figured a simple decorticated coral from Kentucky 

 as Cyathophyllum plicatum* The septa are stated to be somewhat thick- 

 ened, not converging regularly at the center, hut folded and twisted. 

 A few pages later, but in the same list of new species of the genus 

 Cyathophyllum, he described an essentially different coral from Sweden 

 and inadvertently assigned to it the same name. Cyathophyllum plicatum.^ 

 Perceiving his error, the name of the latter form was subsequently 

 changed to C. perfoliatum on the manuscript in the museum of the 

 university of Bonn.'! 



This Swedish coral was thus originally described : 



"Top-shaped, simple and free. Thecells proliferating from the center are funnel- 

 shaped and thin, show a radiate regular folding instead of radial lamellae, and are 

 partly free at their edges, partly grown together in layers. This coral shows most 

 clearly the cell structure of this genus." 



The excellent figure given shows the coral to differ very essentially 

 from Cyathophyllum as at present characterized. 



In 1831 Ehrenberg presented a paper to the Berlin Akademie der 

 Wissenschaften, in which he refers Cyathophyllum plicatum, C. ceratites, C. 

 ih cuosum, C. vermiculare, C. secundum,, C. lamellosum and C. placentiforme, 

 all of Goldfuss, to Strombodt s of Schweigger.§ Aside from the fact that 



* Petrefaeta Germanise, erster theil, 1826; page 51, tab. xv, fig. \2. 



fPage 59, tab. xviii, fig. 5. 



X Monographic des Polypiers Fossiles des Terrains Pala;ozoi'qui - 1851, Edwards and Haime, page 

 405; Histoire Naturelle des Coralliaires, Milne-Edwards, tome troisiAme, 1860, p. on. 



-, Beitritge zur physiologischen Kenntniss der Oorallenthiere im allgemeinen, und besonders dea 

 rolhen Meeres, nebs! einem Versuche zur physiologischen Systematik derselben : Abhandlungen 

 der Koniglichen Akademie der Wissenschaften zu Berlin, 1832 1 1 • 1 1 



