DEVONIAN FISHES OF IOWA 



265 



Remains of this small and highly ornamented species occur 

 rather abundantly in a well marked horizon in central Ken- 

 tucky, being embedded in phosphatic nodules, vast quantities of 

 which are carried by a continuous layer less than two feet thick 

 and distributed over a wide area. This horizon marks the very 

 base of the Waverly series, and rests conformably upon the 

 evenly bedded Devonian Black Shale, whose age corresponds 

 with the Genesee shales of New York State.* The phosphatic 

 nodules near Junction City and elsewhere in Boyle and Marion 

 counties carry an extensive fish and invertebrate fauna, besides 

 a considerable quantity of fossil wood. As a result of system- 

 atic collection made at the principal localities during the last two 

 or three years, chiefly by Mr. Moritz Fischer, a large supply of 

 material has been brought together, the greater part of which is 

 now owned by the Museum of Comparative Zoology at Cam- 

 bridge, and the American Museum of Natural History in New 

 York. Cordial thanks are here rendered to Dr. Bashford Dean, 

 in whose honor the new species under discussion is named, for 

 the generous loan of all the most valuable and instructive speci- 

 mens in his custody. 



It is to be regretted that no completely preserved individual 

 of the new species has yet been brought to light, although from 

 amongst a large series of nodules it is possible to reconstitute 

 nearly all the different parts and to restore the general outline. 

 The part most commonly preserved, and that, too, with a per- 

 fection and fidelity of detail that extends even to soft tissues 

 and hence may be compared to the process of embalming, is the 

 head portion. And by this is to be understood the complete 

 head, since the combined lot of specimens presents for study 

 the cranial ; roof , facial plates, branchiostegals, jaw-parts, brain 

 structure, internal ear, nerve endings and arterial blood vessels. 

 A complete head exposed so as to be visible from both sides and 

 from below, and remaining in natural association with the pec- 

 toral fins and a portion of the trunk, is preserved in the Ameri- 



* Knott, W. T. 

 ress, Geol. Surv. 



Report on the Geology of Marion County. Reports of Prog- 

 Kentucky (1885), p. 21. Girty, G. H., Description of 



faunas in the Devonian Black Shale of Eastern Kentucky. Amer. Journ. Sci. 



1898, ser. 4, 6, p. 384. Foerste, Aug. F., The Silurian, Devonian and Irvine 



Formations of East-Central Kentucky. Bull. no. 7, Kentucky Geol. Surv. (1906), 



p. 110. 



