692 HISTORICAL GEOLOGY. 



Myriapods, Arachnids, and Insects of the world, with references to all published papers 

 and works on the subject, covering 744 octavo pages. 



13. Vertebrates. — (a) Fishes. — Ganoids. 'Fig. 1100, Eiirylepis tuberculatal^eyvh.; 1101, 

 Codacanthus elegans Newb., Linton, Ohio, remarkable for not having the tail heterocercal, 

 although strictly vertebrated ; 8 other species of Eurylepis, 2 of Coelacanthus, and 3 of 

 Hhizodus, have been described by Newberry from Linton, also Palceoniscus scutigerus 

 and P. peltigerics l^ewh., Ohio ; P. Leidyanus L>ea, Fa,. ; P. gracilis 'N.&W., III.; P. Broicni 

 of Albert Coal iline, N. B.; P. Jacksoni Dn. Other Ganoids occur, of the genera Mega- 

 lichthys, Amblypterus, Pygopterus, and Bhadinichthys, in the Coal-measures of the United 

 States and Nova Scotia. 



Among Selachians, the following European genera have been recognized in the Coal- 

 measure limestones of Pennsylvania, Ohio, Indiana, Illinois, etc., — the species being gen- 

 erally distinct from those of the Old World : Diplodus, Cladodus, Orodus ; Diplodus com- 

 pressus Newb. , Linton, Ohio ; D. latus Newb. , ibid. ; D. gracilis Newb. , ibid. ; Petalodus, 

 Ctenoptychius, Chomatodus ; Fig. 1102, Petalodus destructor N. & W., from Illinois ; 1104 a, 

 1104 h, Petrodus occidentalis N. & W., from Illinois, Indiana, etc. ; 1103, fin-spine found 

 associated with the scales of Petrodus occidentalis, and referred by F. H. Bradley to the 

 same species. Cholodus, Peltodus, Calopodus, Ctenoptychius are other genera. Of fin- 

 spines, there are Orthacanthus arcuatus Newb., Linton; Comj^sacanthus Icevis Newb., 

 Linton; Drepanacanthus anceps N. & W., from Springfield, 111., and others. 



The genera of the Subcarboniferous are in part represented among the Carboniferous 

 species, as Diplodus, Orodus, Cladodus ; Petalodus (Fig. 1102, P. destructor N. & W., 

 111.), Petrodus (Fig. 1104 a, b, P. occidentalis, N. & W., 111., Ind., etc.), Ctenoptychius, 

 Chomatodus, Deltodiis, Pcecilodus, Xystrodus. Besides, there are 4 species of Agassizo- 

 dus, all from the Coal-measures. Also fin-spines of the genera Compsacanthus, Drepana- 

 canthus, etc. For figures and descriptions of fossil species the most important volumes 

 are those of the Ohio Geological Report by Newberry, and those of the Illinois Beport by 

 Newberry and Worthen and St. John and Worthen. 



(6) Amphibians. — Fig. 1109, Pelion Lyelli Wyman, Linton, Ohio ; Fig. 1108, Amphi- 

 bamus grandiceps Cope, Morris, 111.; Fig. 1110, vertebrse and ribs from Linton, figured by 

 Wyman, but not named, referred by Cope doubtingly to the snake-like Molgophis macrurus 

 Cope. Baphetes planiceps Owen, from Pictou, N.S. ; the specimen is a portion of the skull 

 7 inches broad. The genera Phlegethontia and Molgophis of Cope are referred to Dolicho- 

 soma of Huxley by Fritsch. For descriptions and figures of the species of Ohio, see Geol. 

 Bep., Pal. ii. ; of Nova Scotia, Dawson's Acad. Geol., and its supplement of 1878, the 

 latter containing also figures of Insects, Crustaceans, and Myriapods ; also Supplement of 

 1891, and later in the Trans. Boy. Soc. The Linton layer in Ohio is a local formation of 

 cannel coal at the bottom of the Pittsburg coal-bed, indicating, as Newberry states, lake- 

 like conditions during the j^rogress of the layer. Twenty -three consecutive footprints of an 

 Amphibian, Thenaropus heterodactylus, were found by A. T. King, near Westmoreland, 

 Pa. , in a layer about 100' below the horizon of the Pittsburg coal ; the tracks of the 

 hind-feet 5-toed, and of the fore-feet 4-toed, — the former 5^ inches long, and the latter 

 4^ inches ; and the distance between the successive tracks 6 to 8 inches, and between the 

 2 lines about the same. Another species from the same region is the Chirotherium Beiteri 

 of Moore. 



2. Permian Period. 



On the Permian Flora of West Virginia, etc., see Fontaine and White, I.e.; contains 

 38 plates. The following are the Coal-measure species which continue, according to these 

 authors, into the Permian or Upper Barren Measures of West Virginia and Pennsylvania : 

 Catamites SucJcovi, Sphenophyllum filiculme, Annularia longifolia, A. sphenophylloides, 

 Neuropteris hirsuta, N. flexuosa, N. auricidata, N. cordata, Pecopteris arborescens, P. 



