Geology and Mineralogy. 409 



the plants of beds which had previously been determined, through 

 the animal fossils, to be Cretaceous; and, if geologists finally con- 

 clude that the flora of the Lignitic beds is all Cretaceous, it will 

 be done on the ground of the animal relics, and in spite of what 

 has been regarded as good botanical evidence. 



While then there may be doubts over chronological conclusions 

 from fossils of whatever kind, the geologist who surveys the whole 

 field finds those doubts less weighty than they w^ould naturally 

 appear to one who looked at the subject from the botanical side 



2. Report of the Geological /Survey of Ohio. Volume II. 

 Geology and Palceontology. — Part. II, Palmontology, (or, as 

 stated on the cover, Paleontology, Vol. II.) 436 pp. roy. 8vo, 

 with over sixty plates. Columbus, Ohio, 1875.— This large volume 

 contains, after a preface, by Dr. J. S. Newberry, the head of the 

 survey, descriptions of Fossil Fishes, by Dr. Newbeeey, pp. 1-64 ; 

 of Silurian Fossils, a?id of Crinoids from the Waverly group, by 

 J. Hall and R. P. Whitfielb, pp. 65-179 ; of Silurian and Devo- 

 nian Corals, by H. A. Njcpiolson, pp. 181-268; of Invertebrate 

 Carboniferous Fossils, by F. B. Meek, pp. 269-347 ; of Carbonif- 

 erous Amphibians, by E. D. Cope, pp. 349-411; of Lower Car- 

 boniferous fossil plants, by E. B. Ajjokews, pp. 413-426. The 

 paleontological work was thus in able hands, and covers a large 

 number of species in each of its departments. The portions giv- 

 ing the most novel results are those of the Fishes and Amphibians, 

 and the Lower Carboniferous plants. 



Dr. Newberry describes the genus Dinichthys from new and 

 magnificent specimens — including broad plates of the venter and 

 back, fifteen inches to two feet in length, a mandible twenty-two 

 inches long, a cranium almost complete, and other bones — and 

 shows that it was closely related to (Joccosteus. The large ven- 

 tral pieces were five in number. The anterior end of the mandi- 

 ble was turned up so as to form a strong acute prominent tooth, 

 which had a produced dentate margin in one species. The <k'n- 

 tition resembles that of the living Lepidosiren ; and Dr. New- 

 berry refers the genus (along with Coecosteus, Heterostius, As- 

 terolepis, Pterichthys, etc.), to the Lepidosiren group, or the Dip- 

 noa, and agrees with Dr. Gflnther in placing the Dipnoans and 

 Placoderms with the Ganoids. A species of Coecosteus, C\ ocei- 

 dentalis Newb., is described from Ohio. Dr. Newberry describes 

 "Conodonts" from the Waverly group, which he is inclined to 

 refer to the Marsipobranchs. He also gives new species of 6Va- 

 dodus, Polyrhizodus, Orodus, Ctenacanthm.Lystracanthus Platy- 

 odiis, Phynchodus, (Jtenodm, Bipteriis, and introduces the new 

 genus of Ganoids, Seliodus, for species near those of Dipterus. 

 Dr. Newberry, after remarking that the occurrence together of the 

 spines Ctenacanthus furctcarinatus, the teeth Orodus variabilis, 

 and certain dermal tubercles, show that they belong to the satne 

 ■ ' ' tail, with 



