BUFFALO , SOCIETY OF NATURAL SCIENCES 



37 



right suborbital; the larger part of the left mandible; an 

 imperfect antero-superognathal; impression of a postero- 

 superognathal; larger portion of the dorsomedian; an 

 anterior, and both posterior ventrolaterals; the postero- 

 ventromedian ; a spine-like element, and portions of a 

 lateral or "clavicular" plate. 



Formation and Locality. — Basal concretionary portion of the Rhine- 

 street shale (Portage); Eighteen Mile Creek, near Hamburg, Erie 

 County, N. Y, Collected by W. L. Bryant and Frederick Houghton. 



Fig. 7. Concretion Containing the Type of Dinichthys magnijiciis , as Found 



Near base of Rhinestreet shale (Portage); Eighteen Mile Creek, near 



Hamburg, N. Y. 



A species as large as Dinichthys terrelli, ornamented with very small, 

 and mostly closely-crowded, non-stellate tubercles; distinguished 

 especially by the forms of the head and the mandible. Head nar- 

 rower anteriorly than in any other species ; its outline, when viewed from 

 above, sub-triangular; preorbital margin rounded; median occipital 

 short but very broad, and tripartite along its anterior margin. Lat- 

 eral lines traversing the preorbital gently curved outward at their 

 anterior extremities and not reflexed into curves concave toward the 



