DEVONIAN FISHES OF IOWA 



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Fig. 30. 



Fig. 30. Protitanichthys fossatus Eastm. Delaware limestone (Ulsterian) ; Delaware, 

 Ohio. Restoration of headshield showing transversely elongated pineal and rostral plates , 

 and sinuous suture-line between the centrals. Letteringasin preceding figures, x i. Holo- 

 type in Museum Comparative Zoology. 



the very conspicuous pineal foramen, placed slightly behind the 

 middle of the plate it pierces. Two other prominent fossae, 

 corresponding to those in Dinichthys, occur in line with the 

 pineal on the visceral side of the preorbitals, and these appear 

 to have been bounded by a low transverse ridge in front. The 

 assumption does not appear to be unreasonable that these fossae 

 served to receive the bases of vomerine teeth. 



Formation and locality. Delaware limestone (Ulsterian) ; 

 Delaware, Ohio. Holotype preserved in the Museum of Com- 

 parative Zoology, Cambridge. 



Genus TITAMCHTHYS Newberry. 



Plates of head and trunk resembling those of Dinichthys, but 

 relatively thinner, and more laterally expanded. Pineal plate 

 elliptical, broader than long, in contact with the centrals, and 

 pierced by one or two foramina, the latter sometimes capped 

 by a small bony operculum. Lower dental plates long and slen- 

 der, without denticulations, grooved in the anterior portion of 



