Ravmom) : 15kaliik)|'()1)a an'd ()siraco1)A oi' thk Cha/v. 227 



The genus Protarhyucha was proposed by Hall and Clarke to in- 

 clude primitive Rhynchonelloids, and Atrypa ditbia was designated 

 as the t>pe. In a foot-note appended to their description, the authors 

 of the genus remark that the details of the generic description have 

 been drawn from specimens identified as Atrypa dubia, but collected 

 in the gorge of the Kentucky Ri\er at High Bridge, Kentucky. Tiie 

 specimens referred to are in the pri\ate collection of Prof. Charles 

 Schuchert, and an examination of them shows that they are different 

 from an>thing the writer has seen in the Chazy. Hall and Clarke 

 did not figure any specimens of Protorhyncha from the Chazy, nor did 

 they figure the specimens from High Bridge which they referred to 

 that species. As an example of Protorhyncha they figure Atrypa 

 equiradiata Hall from the Clinton, but Schuchert, in his "Synopsis 

 of American Fossil Brachiopoda" (Bulletin U. S. G. S., No. 87), has 

 referrred this species to the genus Caniarotecchia. The only other 

 species mentioned by Hall and Clarke is Poramhonites ottawaensis 

 Billings, from the Black River, but this species appears to be a Rhyn- 

 chotrema. Camarella antiqiiata Billings was referrred to Protorhyncha 

 in Schuchert's "Synopsis," but that species has recently been made 

 the type of the genus Sicantonia by Walcott. (Proceedings U. S. 

 National Museum, \'ol. XX\TII, p. 296, 1905.) Camarella{?) minor 

 Billings is also doubtfully referred to Protorhyncha in the "Synopsis," 

 but with the comment that it may be the type of a new genus. Dr. 

 Walcott evidently thinks it a Swantonia (loc. cit.). 



It seems then that the name Protorhyncha must be reserved for the 

 shells from the Stones River formation at High Bridge, Kentucky. 

 from which Hall and Clarke drew their generic diagnosis. This is 

 the species identified by Ulrich as Protorhyncha ridleyana (SafTord). 

 (Geologic Atlas of the United States, Columbia Folio.) 



Super-family SPIRIFERACEA Waagen. 



P^amily ATRYPID.F: Gill. 



(ienus Zygospira Hall. 



II. Zygospira (?) acutirostris Hall. 



(Plate XXXIV, figures 15-22.) 

 Airy pa aciitiroslra Hai.l, 1847. Paleontology of New York, \'o!. I, p. 21, PI. 4 

 ' bis, fig. 6. 

 Rhynchonella aciilirostris H.\ll, 1859. Twelftli Annual Report Cabinet Natural 

 History, p. 65. 



