410 Forty-second Report on tee State Museum. 



which are the long-winged forms, and those with few and coarse plica- 

 tions, " which for formations of Devonian and later " (palaeozoic) " age 

 are as characteristic as they are infrequent in those of prse-Devonian 

 age." Gyrtina of very large size, and a septate, high-areaed Spirifer; 

 • a large Megalanteris; Orthids of the type of 0. siriatula; Choneles of 

 large size; Rhynchonellas with few and coarse plications. 



Trilobites: The occurrence (sparse) of Cryphceus; Dalmanites of the 

 type of D. Hausmanni, (Hausmannia) ;* Phacopes with obsolescent but 

 apparent glabellar furrows, and compound pygidial pleurae (P. fecun- 

 dus, etc.), and the absence of all characteristic Silurian genera, e. g., 

 Ampyx, Sphcerexochus, Staurocephalus, Asaphus. 



Cephalopods: Orthoceras of the type of 0. triangulares 0. Jovellani 

 (Jovellania, with subtriangular septal section and marginal sipho); 

 Hercoceras; Gyroceras of the type of G. tetragonum; Nautiline Goniatites 

 (G. subnautilinus, G. latiseptatus, G. neglectus, G. evexus, etc.) a type 

 extending in rare instances, in the Devonian of Europe and America, 

 above the limit of the Middle-Devonian. 



Gastropods: A remarkable development of the Platyceratidae (Gapu- 

 lus, Orthonychia, Hercynella). 



Lamellibranchiata : Pterineas (Actinopteria, partim) Allorisma, 

 Pleurophorus, identical in species with those in the Rhenish Devonian; 

 large, many-ribbed Cardiolas (Panenka). 



Corals: Pleurodictyum, Amplexus, Beaumontia and Ghostetes, the 

 latter similar to, perhaps identical with French and American Lower- 

 Devonian species. 



Though these Devonian elements prevail, there are, on the other 

 hand some important Silurian features. Among the brachiopods, Spi- 

 rifers with low, indistinct plications and finely, radiately-striated shell 

 (type of S. plicatella, S. radiata-\) ; Pentamerus* of the type of P. Knighli. 



Rhynchonellas with numerous fine plications. Among the trilobites, 

 Bronteus with smooth aspinous margin. The cephalopods have two 

 species identical with the Bohemian typical Silurian, E. Of the 

 lamellibranchs, Gardiola interrupta, so widely diffused in the Upper- 

 Silurian. The surprising Graptolite fauna is confined to the upper 

 horizon of the Hercynian beds. Eight species are identified, all with 

 a single row of cells (Monograptus). This element is regarded not as 

 nullifying the positive Devonian expression of the underlying fauna, 

 but as serving to emphasize its great age. 



* More properly this character may be regarded, not as diagnostic of the Silurian or 

 Devonian in their typical development, but as one of the most important peculiarities 

 of the Hercynian constitution. 



t Spirifer Davousti&nd Pentamerus rhenanus, species following these types respectively 

 aro from the Lower-Devonian. 



