134 PALEONTOLOGY OF NEW YORK. 



Subgenus CCELOSPIRA, Hall. 186:1 



PLATE LIII. 



1839. Atrypa, Sowerby. Murchison's Silurian System, p. 637, pi. xx, fig. 7. 



1841. Atrypa, Conrad. Geol. Siirv. N. Y.; Ann. Rept. Palaeont. Dept., p. M. 



1813. Atrypa, Hall. Geolog-y of N. Y. ; Rept. Fourth Disl., p. 71, fig. 4. 



1852. Atrypa, Hall. Paleontology of N. Y., vol. ii, pp. 74, 75, pi. xxiii, figs. 9-11. 



1855. Hemithyris, McCoy. British Pal.'eozoic F"ossils, p. 201. 



1857. Ltptoccelia, Hall. Tenth Ann. Rept. N. Y. State Cab. Nat. Hist., p. 107. 



1859. LeptocceUa, Hall. Paljeontology of N. Y., vol. iii, p. 24.'5, pi. xxxviii, figs. 1-7. 



1863. Ccclospira, Hall. Sixteenth Ann. Rept. N. Y. State Cab. N.it. Hist., p. 60. 



186(5. LeptocceUa, Billings. Catalogue of Silurian Fossils of Anticosti, p. 48. 



1866. Atrypa, Davidson. British Silurian Brachiopoda, p. 136, pi. xiii, figs. 23-30. 



1867. Ccelospira, LeptocceUa, Hall. Palaeontology of N. Y., vol. iv, pp. 328-330 (fig. 1), 365, pi. Hi, 



tigs. 13-19 ; pi. Ivii, figs. 30-39. 

 1884. LeptoccBlia, Davidson. General Summary, p. 424. 



The term Ccelospira was proposed in the Sixteenth Annual Report of the 

 New York State Cabinet of Natural History (p. 60) for the Lower Helderberg 

 species C. concava, Hall, which originally had been referred* to the genus Lep- 

 TOCCELiA. The reason for the separation was expressed in a figure of the bra- 

 chial apparatus accompanying the first use of this name. The spirals were 

 represented as loosely coiled and almost in the same plane, the apices being 

 very slightly elevated and directed outward ; the loop posteriorly situated, 

 broad and continuous, very similar to that of Zygospira. The I^eptocalia concava 

 is a small piano-, or subconcavo-convex shell, covered with rather numerous 

 simple or bifurcating plications. The pedicle-valve has distant teeth arising 

 from the lateral cardinal slopes, and in front of the umbonal cavity are a pair 

 of rather deep oval diductor scars, which embrace the anterior extremities of 

 two narrow, less excavated adductors. These are separated by a narrow, more 

 or less conspicuously developed median ridge as in Terebraiula venusta and 

 T. lepida. 



The cardinal process has the same structure as in Anoplotheca, consisting of 

 a central portion curved backward to, or slightly beyond the hinge, and faintly 

 bilobed on its posterior extremity. The crural bases are consolidated with the 

 central process and are continuous with the socket walls. There is a stout 



* Paleontology of New York, vol. iii, p. 245, 1859 ; and Tenth Rept. N. Y. State Cabinet, p. 107, 1857. 



