PALEOZOIC TIME — DEVONIAN. 



617 



Chemung of Erie County, Pa. It is the ProtoUmtdus Eriensis of H. S. 

 WiUiams. 



7. Vertebrates. — Remains of Placoderms, of the brachiate type, or re- 

 lated to Pterichthys, have been found in Ohio and in the Catskill sandstone 

 of Kew York and Pennsylvania, and nearly perfect specimens (Figs. 960, 



960 a) of one species, Bothriolepis Canadensis of Whiteaves, at Scaumenac 

 Bay (in Bale de Chaleurs), jSTew Brunswick. Fig, 960 is a view of the dorsal 

 shield, and 960 a, the ventral, both reduced to a third of the natural size ; 

 and 960 shows also the probable outline of the posterior extremity, which 

 has been added to Whiteaves's figures from the form in Pterichthys. Fig, 



961 represents, natural size, the finger-like termination of a fore limb of 

 possibly the same species, described by Cope, which was found at Mansfield, 



965-969, 



DiPNOAN Fishes. — Fig. 966, Dinichthys Hertzeri, front view of . jaws (x ^)\ 966, ventral plates (x,^^); 967, palate 

 tooth of Dipterus Sherwoodi ; 968, Id. of Ctenodus Nelsoni : all from Newberry. Fig. 969, Phaneropleuron 

 curtum (x|), from Whiteaves. 



Tioga County, Pa., with remains of Holonema. Fig. 962 represents a plate 

 of Bothriolepis from the Catskill beds, 



No remains of the posterior scaly part of the body have been observed in 

 connection with specimens of the American species of Bothriolepis, though 

 occurring in Scotland with those of Pterichthys. 



