of North America with those of Europe. 22 1 



Remarks upon the Palceozoic Fossils common to America and 

 Europe, and upon the relations which they offer in their dis- 

 tribution. 



Holoptychus yiobilissimus, (Agass.)— This fish, characteristic 



of the old red sandstone of Scotland, England, and Russia, is 



found at Blossburgh, in Pennsylvania, in the thick stage of 



the sandstone which forms the superior part of the Devonian 

 system. 



Dendrodus, (Owen.)— We think we are able to refer to this 

 species the tooth figured by Mr. Hall in his final Report on the 

 Geology of New York, (page 281, fig. 4,) and found at Bloss- 

 burgh with the preceding species. The genus Dendrodus is 

 characteristic of the old red sandstone of Scotland, and the De- 

 vonian beds of Russia. 



Asterolepis, (Eichw.) — We refer to this genus two fragments 

 °f American fishes; one which we have seen in the collection 

 of Mr. Gebhard, # and which he told us had been found in the 

 calcareous sandstone of Schoharie, and the other which we pur- 

 chased, and which appears to have come from the Hamilton 

 slates. This last presents no points of difference from the speci- 

 men which I found in the Eifei. 



^ Calymene Blumenbachii, Brong. ; C. senaria, Conrad.— Mr. 

 Conrad has given the name of C senaria to a variety of C. Blu- 

 menbachii which is found in the most ancient palaeozoic beds, 

 (the Trenton limestone and the blue limestone of Ohio,) which 

 ■ distinguishable from the species of M. Brongniart only by the 

 contraction of the front part of the middle lobe of the head ; a 

 character which allies it, in some degree, with the C. Tristani. 

 Fhe true C. Blumenbachii unquestionably exists in America in 

 { he upper Silurian system, {Clinton and Niagara groups.) Its 

 var. major figured by Murchison, (Silurian system, plate 7, fig. 6,) 

 a nd named by Mr. Green C. platys, would be found according 

 f° this author m the calcareous sandstone of Schoharie. If this 

 ls so, this variety which belongs in England to the Ludlow stage, 

 m ust have lived in America in beds which we consider a little 

 ^ore recent.f 



The collection of Mr. John Gebbard, Jr , is one of the richest for the term of 

 r °CK 8 and fossils which constitute the hills of the H elder berg around Schoharie, 

 ar, d it s owner does himself pleasure in making it n< < r^.ble for the inspection of 

 dangers. 



rt* [It appears to us that the C. senaria is distinct from C. Blumenbachii of Dudley, 

 1 w Niagara spec] i t which is similar in character, p( - I feature* somewhat 

 pore li j the Dudley specimens. The Calymene platys of Green, win I ocmrs 

 ^Jbe Schoharie grit, is always much larger than either of jN preceding, and pos- 



~- "wmenbachii appearing in the lower Silurian strata very aounaanuv. ana re- 

 hearing in the Niagara group, while during the subsequent deposits of water-June, 



P 



