BRACHIOPODA. * 143 



specimens from New York. The specimens occur in the ordinary limestone but most 

 abundantly in the sandstone phase of the formation. Those from the sandstone are 

 considerably larger than those from the limestone. 



Camarotoechia prolifica (Hall) 



Plate 34, figures 1 and 2 



1867. Rhynchonella {Stenocisma) prolifica Hall, Pal. New York, IV, p. 343, pi. 54a, 



figs. 1-10. 

 1894. Camarotoechia prolifica Hall and Clarke, Pal. New York, VIII, pt. 2, p. 192, pi, 



57, figs. 42, 43. 

 1897. Camarotoechia prolifica Schuchert, Bull. U. S. Geol. Surv., 87, p. 168. 

 1913. Camarotoechia prolifica Prosser and Kindle, Maryland Geol. Surv., Middle and 

 Upper Devonian, pp. 173-174, pi. 15, figs. 1-3. 



Hall's description — "Shell subtriangular-ovate; length and width about equal; 

 front rounded, with a shallow sinus and gentle elevation depressed in young shells 

 and becoming gibbous in older ones. 



Ventral valve depressed-convex in the middle, elevated or a little gibbous on the 

 umbo, curving to the sides and gently depressed in. a shallow sinus below the middle; 

 apex slightly incurved. 



Dorsal valve equally convex with the ventral, sometimes a little more convex, 

 the difference increasing with age; regularly convex as far as the middle of the shell, 

 below which the mesial fold becomes more or less elevated, but rarely rises conspicuously 

 above the general outline. 



Surface marked by about twenty to twenty-two, sometimes twenty-four, angular 

 plications, of which three occupy the mesial sinus and four the mesial fold. Sometimes 

 a few imbricating lines of growth are visible, but the finer surface markings are un- 

 known. 



Length usually less than half an inch, and few individuals exceed this. The casts 

 of the interior show short and rather slender lamellae in the ventral valve, and a short 

 septum in the dorsal valve." 



Remarks — Specimens from the St. Laurent are small. The largest in the Walker 

 Museum collection is 10 mm. wide by 9 mm. long. The number of plications ranges from 

 14 to 20. The number of plications in the sinus ranges from. 3 to 5. The plications 

 are not sharply angular. 



Occurrence — St. Laurent limestone from 3 miles south of St. Marys, Perry County. 



Camarotoechia sappho (Hall) 



Plate 34, figures 15, 16 and 17 



1860. Rhynchonella sappho Hall, 13th Rep. New York State Cab. Nat. Hist., p. 87. 

 1867. Rhynchonella (Stenocisma) sappho Hall, Pal. New York, IV, pp. 340-341; pi. 



54, figs. 33-43; pi. 55, figs. 47-52. 

 1894. Camarotoechia sappho Hall and Clarke, Pal. New York, VIII, pt. 2, p. 192, pi, 



57, figs. 10-14. 

 1897. Camarotoechia sappho Schuchert, Bull. U. S. Geol. Surv., 87, p. 168. 

 1901. Camarotoechia sappho Kindle, Indiana Dept. Geol. Nat. Res., 25th Ann. Rep., 



p. 584, pi. 7, fig. 4. 

 1909. Camarotoechia sappho Grabau and Shimer, North American Index Fossils, I, 



p. 288, fig. 354, c. d. 

 1913. Camarotoechia sappho Prosser and Kindle, Maryland Geol. Surv., Middle and 



Upper Devonian, pp. 174-175, pi. 15, fig. 4. 

 Hall's description — "Shell, in full-grown individuals, transverse, gibbous, sub- 

 elliptical. Young shells broadly subtrigonal becoming short-ovate; nearly straight in 



