NAPLES FAUNA IN WESTERN NEW YORK, PART 2 323 



P. n a t a t o r, and here the name is used without qualification. 1 Though 

 here employed for a fossil from the soft Portage or Cashaqua shales which 

 had been determined by Hall in i843 2 as Bellerophon expansus? 

 Sow., the name now takes on a new value. The description is a very clear 

 characterization of the species, and it is here cited as from the shales on 

 Cashaqua creek. 3 Waagen employed the term Phragmostoma, 4 but failed 

 to make a clear' generic distinction between that division and Patellostium, 

 then introduced as new, for seamless forms having a greatly expanded 

 flaring aperture. The type species taken for the latter genus was F. 

 Roemer's Bellerophon macrostoma. De Koninck employed 

 the term Phragmostoma with P. natator as type, which, as observed, 

 is not the original application of the term. Koken likewise has made 



'In the explanation to plate 6 of this work, Hall referred three of the figures (12-14) 

 to this species which are not P. natator but P. c y m b u 1 a. (See the correction of this 

 error in Pal. N. Y. v. 5, pt 2, p. 108). 



2 Geology of New York; rep't on fourth dist. p. 244, fig. 3. 



3 It is also stated to occur in the "shales of the Hamilton group in Chenango county." 

 This may either be a locality in the Hamilton beds or in the Ithaca beds, for the fossils of 

 the latter were for years confused with those of the beds below. For ourselves, we have 

 never seen the species from any locality of either formation. 



The Ithaca (Central Portage) fauna does however contain a species, suggestive of 

 Bell, patulus in general proportions and size, with broadly explanate aperture, but 

 with a definite slit band and a very distinct, flat, unthickened transverse plate across the 

 opening from the inner lip. 



The cuts on plate 16 show the nature of this septum, its doubly crescentic inner 

 margin and the longitudinal impressed line which divides it medially, forking proximally 

 and probably receiving the inner whorl in the fork. The outer surface apparently bore 

 faint revolving lines in pairs as in Bell, leda of the Hamilton fauna, but these do not 

 always manifest themselves on sculpture casts. Bellerophon leda is devoid of 

 septum or greatly calloused lip. We see no reason for not regarding this species as a 

 genuine Carinaropsis, even though shells of the genus have not been observed before in 

 faunas later than Lower Siluric. This shell is figured under the designation Carina- 

 ropsis ithagenia. 



4 Paleontologia Indica. ser. 13. 1880. pt 2, p. 131. 



