1883.] NATURAL SCIENCES OF PHILADELPHIA. 213 



NOTE ON A COLLECTION OF FOSSILS FROM THE HAMILTON (DEVONIAN) 

 GROUP OF PIKE CO., PA. 



BY PROF. ANGELO HEILPRIN. 



Among a small collection of invertebrate fossils obtained from 

 the Hamilton rocks of the vicinit}' of Dingman's Ferry, Pike Co., 

 by Drs. E. C. Hine and J. Holt of this city, and now in their 

 possession, I have been able to identify the following species 

 and genera. Most of these are probably not new to the State, 

 but inasmuch as the palEeontology of Pennsylvania has been but 

 very imperfectly (indeed, one might say, not at all) worked up, 

 and the fossils there occurring, although known in some part to 

 amateur collectors, but very S[taringly recorded, it has appeared 

 to the writer that the publication of the present list, as well as of 

 others of a similar character to follow, may not prove entirely use- 

 less, tending toward a more complete knowledge of the extinct 

 fauna of the State. 



ACTINOZOA. 



Heliophyllum Halli. 



Mollusc A. 



i^e»es/e/Za, sp. indet. Aviculopecten duplicahis? or 



Crania Hamillonise. A. scabridus ? 



Spirife.i- mucronatus. Limoptera macroptera. 



Sjjirifer granuliferus. Paracyclas lirata. 



Sijirifer medialis? Grammysia hisulcata. 



Sti'eptoi'hynchus Chemimgeyisis. Orthoceras (impression). 

 Orthis^ sp. indet. Nautilus or Goniatites (septal 



Ghonetes^ sp. setigera ? lines too imperfectly preserved 



for generic determination). 



Crustacea. 

 Phacops bufo, a complete specimen and several tail-pieces. 

 HomalonotuH Dekayi, several well-preserved fragments unques- 

 tionably' belonging to this species. 



"Crinoid stems or impressions belonging to several distinct 

 species are common in the rock-masses. It may be noted that 

 Prof. I. C. White, during his survey of Pike and Monroe counties, 

 was unable to discover any traces of trilobites in the rocks of this 

 series. " Not a single specimen of a Trilohite was observed in all 

 this thickness of rock at the many localities where it is exposed 

 for observation within the district" (Second Geological Survey of 

 Penns3'lvania, Report of Progress, G 6, p. 112, 1881). 



