30 UNIVERSITY OF MISSOURI BULLETIN 



Rhadinichthyids (Plate I, figs. 1-6) 



At least three species of Rhadinichthys from the Ohio shales 

 are in the Oberlin College collection. Two species, the scales 

 of which are shown in figs. 3 and 5, are from the lower fifty 

 feet, and one species occurs in the top five feet. Several hundred 

 scales of the specimen shown in plate I, figs. 1-4, are pre- 

 served and they are all of the same type. This indicates that 

 scales that are distinctly different represent different species. 

 The remains shown in plate I seem to be complete enough for 

 specific description but such description should await a study of 

 the types. 



Ostracoderm, gen. et sp. undet. (Plate I, fig. 14) 



About fifty feet from the top of the Ohio shales on French 

 Creek near Lorain, Ohio, the writer collected a p'ate which 

 seems to be an antero-dorso-median of an ostracoderm. The im- 

 pression of the plate in the rock is complete but parts of the 

 bone have been lost. The bone is smooth on both sides and is 

 thin and fragile. If a dorso-median may be considered diag- 

 nostic this belongs to an undescribed genus. 



A Unique External Occipital (Plate I, fig. 9) 



About four feet from the top of the Ohio shales a unique 

 external occipital was collected. It is about 40 mm. by 25 mm. 

 in size and at the outer edge has an emargination one centimeter 

 deep. The socket into which the ball of the antero-dorso-lateral 

 fits is rough and little used. The plate probably belongs to a 

 young ind,vidual of an undescribed form. 



Dinichthys Terrelli Newberry (Plate III) 



The photograph of Dinichthys terrelli is of the specimen 

 that furnished data for the writer's restoration of that species 

 published in the Ohio Naturalist in 1908. The skull is flattened 

 and the suborbital, clavicular, and dorso-laterals lie in the 



