EASTMAN: THE DINICUTHYIDS. 41 



It is evident from the figures of the type specimen of D. ringuebergi ^ that 

 the carinal process has been considerably eroded, and the diagram of the infe- 

 rior surface is not wholly accurate. If the anterior margin is entire, as repre- 

 sented for this species, it covers the region back of the head almost as completely 

 as in Coccosteus. The type specimen is preserved in the private collection of 

 its first describer, Mr. E. N. S. Ringueberg, at Lockport, New York. All of 

 the specimens discovered bj' Mr. Mixer that are mentioned in the present 

 paper are preserved in the collection of the Buffalo Society of Natural Sciences. 



Another very beautii'ul example of a young Dinichthyid is preserved in the 

 Museum of Oberlin College, and through the courtesy of Professor A. A. 

 Wright we have been enabled to reproduce a photograph of it, shown in 

 Plate 5, Fig. 3. It is only about 5 cm. long, and 4.5 cm. in maximum width ; 

 the external surface is non-tuberculated. Unfortunately the terminal process 

 is missing, but the inferior carina is very distinct. It is also seen to be strongly 

 emarginate in front. 



The drawings for Plates 1 to 3 have been executed by Messrs. C. A. King 

 and J. W. Folsom. Plates 4 and 5 are reproduced from photographs of the 

 original specimens, taken by Dr. T. A. Jaggar, Jr., excepting Figure 3 of 

 Plate 5. 



1 Amer. Joum. Science, [3], Vol. XXVII. p. 477, June, 1884. 



