Maryland Geological Survey 351 



Camarotcechia (?) altiplicata (Hall) 

 Plate LXIII, Figp. 5, G 



Rhynchonella altiplicata Hall, 1857, Tenth Ann. Rept. N. Y. State Cab. Nat. 



Hist., p. 72, figs. 1-4. 

 Rhynchonella altiplicata Hall, 1859, Nat. Hist. N. Y., Pal., vol. iii, p. 2.31, pi. 



xxxiii, figs. 2a-2fc. 

 Rhynchonella altiplicata Waller, 1903, Geol. Surv. N. J., Pal., vol. iii, p. 282, 



pi. xxix, figs. 24-27. 



Description. — " Shell subtrigonal, more or less gibbous : ventral valve 

 depressed convex ; beak pointed, arched or nearly straight : dorsal valve 

 the larger, most elevated in the middle, declining with a curved outline 

 towards the beak and margins; beak incurved; foramen triangular, ex- 

 tending to the apex of the beak. Surface marked by from ten to about 

 nineteen simple, strongly elevated, sharply angular plications on each 

 valve ; two to four of which are elevated on the dorsal valve into a more or 

 less distinct mesial prominence extending nearly to the beak, and from 

 one to three depressed on the middle of the ventral valve into a distinct 

 sinus, which widens regularly and somewhat rapidly from near the beak 

 to the front, where it is prolonged into a short projection, filling a corre- 

 sponding sinus in the front of the opposite valve: shell traversed by fine 

 concentric lines of growth." Hall, 1857. 



The southern specimens never attain the large growth seen in New York 

 examples. Weller states that it is found only in the Coeymans in New 

 Jersey, the individuals always being smaller and with but a single plica- 

 tion in the sinus. 



Occurrence. — Helderberg Formation, New Scotland Member. 

 Corriganville, Devil's Backbone, Ernstville, Maryland; Cherry Eun, 

 West Virginia. 



Collections. — Maryland Geological Survey, U. S. National Museum. 



Camarotcechia oriskania n. sp. 



Plate LXIII, Figs. 7, 8 



Description. — This small rhynchonelloid has the essential characters of 

 C. altiplicata, except that the dorsal fold has but two plications and the 



