Prof. J. S. Newberry — Devonian and other Fishes. 523 



the Champlain Valley 350; at Montreal 500; in Labrador 800; 

 at Davis Strait 1000 ; and at Polaris Bay, as reported by Dr. Bissell, 

 1600 feet above the ocean-level. 



These clays contain Arctic shells from New York to Greenland, 

 and hence are shown to have been deposited during the Ice Period. 



The elevation of the northern portion of the Continent during the 

 Tertiary — when land connection existed between America and Asia, 

 and between America and Europe, while a mild climate prevailed at 

 the north — and the depression of the northern half of the Continent 

 during the Ice Period, make it impossible to accept the Lyellian 

 hypothesis of topographical changes as causes of these differences of 

 climate, and compel us to look to some extraneous influence for the 

 cause of the cold of the Ice Period. 



24 — On the recent Discovery of New and Remarkable Fossil 

 Fishes in the Carboniferous and Devonian Eocks of Ohio 

 AND Indiana. 



By Prof. T. S. Newbebjiy, Columbia College, New York. 



THE fishes described by Dr. Newberry consisted of: — 

 1. Two new species of Dim cJithys horn the Huron Shale (Upper 

 Devonian) of Northern Ohio. Of these one is considerably larger 

 than either of the two gigantic fishes described in the Geological 

 Report of Ohio under the names of Dinichthys Herzeri and B. 

 Terrelli, the cranium having a breadth of 3 feet 8 inches. This is 

 about one-third larger than the largest specimen of Dinichthys before 

 known, and two or three times as large as Asterolepis of Hugh 

 Miller and Heterosteiis of Pander, its congeners. Another is a 

 small species of Dinichthys, of which the dorso-median plate is only 

 five inches in breadth and six in length. The mandibles are not 

 more than six to eight inches in length, but are much worn by long 

 use, indicating maturity. 



2. The pavement teeth of a gigantic ray, Archceohatis gigas, 

 Newb., from the Lower Carboniferous of Indiana ; the largest tooth 

 is over six inches long by four wide, and one and a half thick. 

 These teeth formed several rows in the mouth above and below ; in 

 shape they resembled the teeth of Psamodus, but the enamelled 

 surface was strongly ridged, to prevent the slipping of mollusks, 

 Crustacea, etc., which formed the food of the fish. 



3. Diplognathtis mirabilis, Newb., a new genus and species, in 

 which the mandibles, set along the anterior portion with conical 

 teeth, diverge at the symphysis, forming a fork which carries another 

 row of strong, acute, recurved teeth. As such a forked jaw would 

 be liable to be split, the rami were united at the symphysis by a 

 strong ligament, deejDly inserted in each bone. This apparatus, 

 admirably adapted to catching slender and slippery fishes, is different 

 from anything hitherto known among vertebrates. 



4. The teeth of several species of Mylostoma, Newb., a new genus 

 of fishes, probably allied to Dinichthys on the one hand, and to 

 Ctenodiis on the other, in which the under jaw was provided with 

 one or more pairs of powerful crushing teeth, somewhat like a shoe- 



