Clarke — Onkonta, Ithaca and Portage Gtroupi 



57 



Melocrinus tricyclus, Eaton (sj>. ). Melocrinus Clarkei, Williams 



Poteriocrinus gregarius? Williams. 

 Taxocrinus Ethacensis, Williams. 



Without further comment, the fundamental difference in these two 

 faunas is apparent, the one (Ithaca) indigenous, whose ancestral stock mani- 

 fests itself in the immediately preceding faunas ; the other exotic and 

 introduced. The latter characterized by its high development of the Groniati- 

 tinae, of Lunulicardium and the cardioconchs, the former by their absence. 

 In fact, there is almost nothing common to the two faunas in their purity, 

 and it is fair to infer that, as suggested above, the few Ithacan species present 

 in the Naples beds, have strayed in from the east.""' 



The Seneca Lake Section. 



The reader who cares t<> follow the detailed description of sections in 

 Schuyler and Yates counties given in the following pages will see nothing 

 more clearly than the westward disappearance of the Ithaca element in the 

 composite fauna of these meridians. 



This lessening of the eastern elements makes itself manifest in the long 

 section made at Havana (Stations XIII and XIV). The rocks of this region 

 are very sparsely fossiliferous and the various substations listed in Havana Glen 

 indicate each a separate association w here species of the two faunas are often 

 present. In following the general trend of the formation to the northwest, 

 into Yates county, a distinct increase in representatives of the Naples fauna is 



* Since this report was written I have received, by the courtesy of Professor G. D. Harris, of Cornell University, a copy of No 

 6, of his "Bulletins of American Palaeontology," dated December 25th, 189(i, and entitled : The Relation of the Fauna of the 

 Ithaca group to the Fauna* of the Portage and Chemung (,pp. 1-50, plate 1), by E. M. Kindle. 



This useful contribution L'ives a review of the succession of fan miles in the Ithaca section and adds considerably to the known 

 lists of species and local manifestations of the faunules. 



These lists show that, with the alterations in appearance of the eastern and western faunas, there not unfrcquently occurs 

 an actual commingling of the species of the two at one plane. They serve also to enforce the importance of the cautionary 

 remarks made above, that an elucidation of the true nature of the faunal constitution in this rock series is not possible without 

 a clear comprehension of the two distinct faunal elements entering into its composition. 



It seems necessary for me to advert here to a single point raised by Mr. Kindle as to the propriety of the term Naples be(/s. 

 which I introduced in 1H85 for the strata which bear the Intumescens fauna. It is observed that Professor II. S. Williams, in 

 describing the lower Chemnng fauna at High Point, in the town of Naples (American Journal of Science, vol. xxv. p. 97, 18C3', a 

 fauna which appears at several hundred feet above the first clear manifestation of the Chemnng fauna In that meridian, applied to the 

 containing strata the term Naples beds, and that, hence, this term being of totally different Significance from my use of it, its earlier 

 date entitles it to piecedence. I have to confess that this is the first time my attention has been directed to the employment of 

 this term by Professor Williams. Upon turning to his paper " On a remarkable Fauna at the base of the Chemung group in New- 

 York " Uoc. cit.), I find this expression used but once and in the following language : " The author is indebted to the kindness of 

 Professor J. M. Clarke, of Northampton, Mass., and Mr. D. D. Luther, of Naples, N. Y., for the discovery of these Naples beds " 

 ip 97). This is, as Professor Williams himself would doubtless admit, but a casual expression, one of several used in the same 

 paper to express a similar meaning, thus : "The Naples rocks" (p. 97), " the High Point fauna " (p. 97), " the fauna at Hkrh 

 Point" (p. 99). "High Poiut beds" (p. 99). These expressions are each used several times, while "Naples beds" occurs hut 

 once iD the paper and has never been employed since by Professor Williams or any one else with reference to the now wi ill 

 known High Point fauna of the High Point bed), which are, with these terms, quite sufficiently denominated. The term "Naples 

 beds " has come into use, with well defined meaning, as a local name for the strata which carry the fauna of the Intumescens-zone, 

 and the term has been neither conceived nor employed as a geologic designation in any other sense. 



