G42 Systematic Paleontology — Upper Devonian 



Occurrence. — Jennings Formation, Chemung Member. Williams 

 Eoad, on Polish Mountain, 1967. 



CoUeclion. — Marvland Geological Survey. 



Family PTERIIDAE 



Genus ACTINOPTERIA Hall 



Actinopteria cf. epsilon Hall 

 Plate LXIV, Fig. 1 



Actinopteria epsilon Hall, 1884, Pal. of N. Y., vol. v, pt. i, p. 122, pi. xxiii, 

 figs. 4-6, 8. 



Description. — Shell rhomboidal with broad, suberect body. Base 

 bioadly curved, posterior side abruptly rounded. Hinge-line straight, 

 ear small, wing well developed. Left valve normally convex ; right valve 

 depressed. The surface of the former bears distinct, fine radial lines with 

 intercalary additions, all crossed by fine concentric striae. On the right 

 valve the radial lines are subdued and the concentric strife more con- 

 spicuous. 



This is one of many species of Actinopteria Avhich a})peared in the 

 Ithaca beds of iNew York and have definite phylogenetic relations with 

 the abundant A. hoydi of the Hamilton fauna. The occurrence of this 

 type of shell in the Maryland strata is of interest. 



Occurrence. — Jennings ForjMation, Chemung Member. Six miles 

 west of Frostburg, Allegany County. 



Collection. — Mar3dand Geological Survey. 



Actinopteria boydi (Conrad) 

 Plate LXIV, Fig. 2 



Avicula toydii Conrad, 1842, Jour. Acad. Nat. Sci., Phila., vol. viii, p. 237, 



pi. xii, fig. 4. 

 Avicula quadrula Conrad, 1842, Jour. Acad. Nat. Sci., Phila., vol. viii, p. 



243, pi. xiii, fig. 5. 

 Actinoptera boydi Hall, 1884, Pal. of N. Y., vol. vi, pt. i, sec. i, p. llo, pi. xix, 



figs. 2-24. 

 Actinopteria hoydi Grabau and Shinier, 1909, N. Amer. Index Foss., vol. i, 



p. 449, fig. 592. 



