525 



Orthis. 



fig. 3 a, cast of a large specimen with strongly marked scars ; 

 3 &, a mold taken from the cast to show how the inside of the 

 shell looked before it disappeared, but some of the muscular 

 impressions omitted in the drawing. Hall gives other figures, 

 and two of a smaller specimen. — Oriskany. — In Pennsylvania 

 doubtfully identified by Ewing among forms in the Alexander 

 quarry between Julian and Unionville in Centre Co. T4, p. 

 431. Also by Clay pole among White's collections from Grove 

 tunnel, Montour Co. G7, pp. 86, 297,— FiZ 



Orthis nucleus. See Ambocoelia umbonata. VIII h. 

 Orthis oblata. Hall, Pal. N. Y. Vol. 3. 1859. pi. x, figs. 10 c, 



11, 17. low. Held, (with Var. emarginaW.) Found by J. 

 Hall, as Spec. 608-10 (00, p. 234) in Coll. along n. slope of 

 Hogback, Pike Co., Pa. from Lower Helderherg outcrop., VI. — 

 Also by Dr. Barrett in the StormvUle shales above and in the 

 Stormville limestone below the conglomerate which divides 

 the Lower Helderherg formation in Pike Co. (G6, pp. 132, 134). 

 — Also in Aughwick Valley, Huntingdon Co., near Orbisonia, 

 abundant in lower 50' of Lower Helderherg limestone (over the 

 Waterlime beds) T, 41; T3, 126. This and Atrypa reticularis 

 are the two most common fossils in the coral heds (260' beneath 

 the Oriskany) in White's Weaver run section, Hopewell town- 

 ship. T3, p. 156.~ F/. 



Orthis occidentalis, Hall, Pal. N. Y. Vol. 1, 1847. Tren 



(^^^&. flll^ ^^^^l .ASrn^ C.C 210. 



