EASTMAN: CATALOG OF FOSSIL FISHES IN CARNEGIE MUSEUM. 371 



dass die lithographischen Schiefer selbst in grosserer Tiefe abgesetzt seien, so 

 stande doch nach der Walterschen Erklarung der Solnhofener Plattenkalke nichts 

 der Ansicht entgegen, dass die" Fische aus tieferen Gewassern der Nachbarschaft 

 eingeschleppt worden sind." 



15. Microdon itieiri (Thiolliere) . 

 1850. Pycnodus itieri Thiolliere. 



Ann. Soc. Sci. Phys. et Nat. Lyon [2], Vol. Ill, p. 132. 

 1854. Pycnodus itieri Thiolliere. 



Poiss. Foss. Bugey, Pt. I, p. 22, PL VI, and two text-figures, p. 23. 

 1856. Microdon itieri J. J. Heckel. 



Denkschr. K. K. Akad. Wiss. Wien, Math-Natur. CI., Vol. XI, p. 201. 

 1860. Microdon itieri A. Wagner. 



Gelehrte Anzeig. K. K. Akad. Wiss., Vol. L, p. 396. 

 1895. Microdon itieri A. S. Woodward. 



Cat. Foss. Fishes Brit. Mus., Pt. Ill, p. 227. 



Type. — Nearly complete fish; Lyons Museum. 



"A moderately elongated species, attaining a total length of about 50 cm. 

 Maximum depth of trunk contained three times in the length of the head and trunk 

 without caudal fin; head with opercular apparatus occupying only about one-fifth 

 of the total length of the fish. Vomerine teeth closely arranged; those of the 

 medianseriesmuchbroader than long; those of the inner paired series elongated and 

 their axes oblique, each pair alternating with the median teeth but scarcely pressed 

 between these; outer teeth irregularly quadrate, about as broad as long, and very 

 closely arranged. Splenial teeth (according to ThioUiere's diagram) much spaced; 

 those of the principal series two or three times as broad as long, rounded at each end ; 

 those of the innermost series minute, and those of the two flanking series somewhat 

 broader than long, the outer twice as large as those of the inner flanking row. Dorsal 

 fin occupying about half of the back, and anal fin more than two-thirds as much 

 extended as this. Scales apparently confined to the most anterior portion of the 

 trunk." (A. S. Woodward, I. c, Pt. Ill, p. 227). 



The form of the body of this species indicates it to be one of the most primitive 

 of the genus and family, possibly a direct descendant of an ancestral type of Pyc- 

 nodont. It is known only from Cerin, and is not represented in any other than the 

 Lyons Museum. 



' Hennig, Erwin. Gyrodus und die Organisation der Pycnodonten. Paleontogr., 1906, Vol. LIII, 

 p. 200. 



