Report of the State Geologist. 233 



prior to that of Prof. Winchell and three years earlier than that of 

 Prof. Swallow, both the latter become synonyms of S. carleri, Hall. 



Sjm-i/er carteri, as illustrated by Meek, agrees with S. texla, Hall. I 

 have collected that species at Sciotoville, Ohio, the source of Mr. Meek's 

 specimens, and find them to be longer on the hinge-line, with a shorter 

 area compared to the length, than I have ever observed in Syi'ingo- 

 thyris carteri, Hall. The plications are also more numerous; in fact, 

 Sciotoville specimens have shown a greater number than examples of 

 any other species known to me. 



Of Spirifer hannibalensis, Swallow, from the Choteau group of Marion 

 and Pike counties, Missouri, I have seen seventeen specimens. They 

 are somewhat smaller than S. tyj)a, but in other respects agree very 

 well with that species or S. carteri. Meek pointed out the close 

 relationship of Swallow's species with S. typa and S. carteri, while 

 Prof. Herrick was disposed to regard them all equal to S. cuspi- 

 data, Martin. Several specimens show clearly the canal if erous plate 

 between the dental lamellae of the ventral valve. The surface of one 

 specimen from the shales at the base of the Choteau group, shows 

 the surface to have been covered with elevated, perforated, closely 

 arranged pustules. Other specimens from which these pustules have 

 been removed by weathering or other causes, have the surface covered 

 by elongated pits, which are the openings of oblique perforations or 

 canals in the shell substance. This last condition is the one generally 

 met with in all our specimens of this genus, and it led Prof. Hall 

 to give the name Spirifer textus to a species from the Knobstone group 

 of Indiana, because of its resemblance to " twilled cloth." 



Dr. Davidson writes of Syriagothyris typa as follows: * 



"Prof. Winchell discovered in the Carboniferous limestones or 

 Burlington limestone of Burlington, Iowa, a shell indistinguishable 

 in exterior appearance from our Britidh examples of Martin's Anomites 

 cuspidatus, and which, from presenting certain peculiar interior 

 arrangements, had led him to propose for that and similarly con- 

 structed shells the generic name of Syringothyris. To his shell he 

 gave the specific name of S. typa, but an attentive examination of his 

 American type with true British examples of S. cuspidatus led Professor 

 King to remark, ' It may be safely assumed that Syringothyris cuspi- 

 data and S. typa are one and the same species,' and that 'it will 

 necessarily follow that Martin's specific name, having priority, must 

 be adopted in preference to the one proposed by Prof. Winchell.' 

 I entirely concur in the view taken in this matter by Prof. King, 

 after having compared specimens of the American and British species." 



^ a : : . - 



* Supplement to the British Carboniferous Brachiopoda, p. 279. 

 30 



