282 NEW YORK STATE MUSEUM 



ria, even though the greater part of the ligament area lies in the opposite 

 direction. 1 



We propose to distinguish this group of Cardiolas of the Upper 

 Devonic by the term Ontaria (Ungulina suborbicularis Hall, 



type). 



Ontaria suborbicularis Hall (sp.) 



Plate 8, fig. 1-20 



Ungulina suborbicularis and Luc in a? retusa Hall, Geology of New 

 York ; rep't on fourth dist. 1843. p. 243, fig. 106, 2, and p. 246, fig. 107, 4 



C ar d i o m o r p h a suborbicularis Hall, Paleontology of New York. v. 5, pt 1, 

 plates and explanations. 1883. pi. 63, fig. 9, 10 



Edmondia? t en ui striata Hall, Paleontology of New York. 1885. v. 5, pt 1, 

 pi. 63, fig. 9, 10 



Cardiomorpha suborbicularis Clarke, U. S. Geol. Sur. Bui. 16. 1885. 



P- 5i 

 cf . Lucina wyomingensis and Lucina varysburgia Williams, U. S. 

 Geol. Sur. Bui. 41. 1887. p. 44, pi. 3, fig. 13, 14 



The variable aspect of this abundant and characteristic fossil has been 



largely though not wholly responsible for its unfortunate entanglement in 



literature. The original woodcut given in 1843 was a very fair and quite 



recognizable representation of a certain expression of the species, which 



may properly be regarded as typical, if not also normal ; that is a subcir- 



cular shell with central beak, concentrically and sharply lined surface, and 



entire freedom from radial striae or plications. The brief description which 



accompanied it mentioned these features and the occurrence of the shell on 



Cashaqua creek and the shore of Lake Erie. Just such shells do occur 



very commonly throughout the lower beds of the formation from Lake Erie 



to Seneca lake. No subsequent account has been given of this original 



type of shell in any of the volumes of the Paleontology of Nezv York except 



in the preliminary publication of the plates of volume 5 of that work, on 



1 Noetling's observations on the morphology of the lamellibranchs, already referred 

 to, indicate the necessity of readjustment of current views as to the stability of the 

 position of the beak with reference to the animal, and with change of beak the line of 

 greatest zhel) growtli also changes. 



