56 PALEONTOLOGY OF NEW YORK. 



(1) ]8<)2. Lingula, Emmons. Geology N. Y. ; Rejit. Second Disti-ict, p. 267 (not fig. 68). 



('{) 1847. Lingula, (Conrad) Hall. Pateontology N. Y., vol. i, p. 3, pi. i, iig-. 2. 



1847. Orhicula, Hall. Palfeoiitology N. Y., vol. i, p. 290, pi. Ixxix, figs. 9 a, b, e. 



(^) 1860. Lingula, Hall. Thirteenth Kept. N. Y. State Cab. Nat. Hist., p. 76, fig. 1. 



1861. Lingula, Hall. Annual Report Geological Survey of Wisconsin, p. 24. 



1862. Lingula, Billings. Palaeozoic Fossils, vol. i, p. 71, fig. 64. 



1863. Lingula, Hall. Sixteenth Rept. N. Y. State Cab. Nat. Hist., pp. 126, 127, pi. vi, figs. 4-8. 

 1867. Lingiola, Hall. Ti'ansactions Albany Institute, vol. v, p. 103. 



1871. Obolella, Billings. Canadian Naturalist and Geologist, vol. vi, p. 218. 



1871. Obolella, Ford. Amei-ican Journal of Science, vol. ii, p. 33. 



1871. Lingulella, Meek. Proceedings Academy of Natural Sciences, Phila., vol. xxiii, p. 185. 



1873. Lingulella, Hall. Twenty-third Rept. N. Y. State Cab. Nat. Hist., p. 245, pi. xiii, fig. 5. 



1874. Lingulella ? , Billings. Palseozoic Fossils, vol. ii, p. 57, fig. 36. 



(1) 1875. Lingulella (Digimnia ?), Hall and Whitfield. King's Report U. S. Expl. Fortieth Parallel, p. 



206, pi. i, figs. 3, 4. 



1875. Lingulepis, Hall and Whitfield. King's Rept. U. S. Expl. Fortieth Parallel, p. 232, pi. i, fig. 8. 

 1878. Lingulella, Ford. American Journal of Science, vol. xv, p. 127. 



(?) 1878. Lingula, Whiteaves. Amei-ican Journal of Science, vol. xvi, p. 226. 



1882. Lingulella, Whitfield. Geological Survey of Wisconsin, vol. iv, p. 334, pi. xxvii, figs. 6. 7. 



1884. Lingula? , (Matthew) Walcott. Bulletin No. 10, U. S. Geological Survey, p. 15. pi. v. fig. 8. 



1885. Lingulella, Matthew. lUustr. Fauna St. John Group, No. 3, pp. 33, 34. pi. v, figs. 7, 8. 



1886. Lingulella, Walcott. Bull. No. 30, U. S. Geol. Surv., pp. 95, 97, pi. vii, figs. 1, 2 ; pi. viii, fig. 4. 



1887. Lingulella, Walcott. American Journal of Science, vol. xxxiv, j-). 188, pi. i, fig. 15. 

 1889. Lingulella, 'Wazcott. Pj'oceedings United States National Museum, 1888, p. 441. 



Diagnosis. " Shell nearly equivalve, broad-oblong, the ventral valve pointed, 

 with a distinct pedicle-groove. Muscular scars strong, nearly as in Obolus, but 

 the pair of anterior retractors are more linear and the sliding muscles small, 

 and not quite external as in Obolus" (Salter. Memoirs Geological Survey of 

 Great Britain, vol. iii, p. 333. 1866). 



Type, Lingulella Davisi, McCoy. 



" The name Lingulella was first introduced about 1861, with the late Dr. 

 S. P. Woodward's full consent; and the name appears at p. 9 of Sir Roderick 

 Murchison's Address to the Geological Section of the British Association, 

 Manchester, 1S61 ; but it is only in Mr. Salter's Appendix to the ' Memoir on 

 the Geology of North Wales,' that the genus is for the first time described" 

 (Davidson, British Silurian Brachiopoda, p, 55. 1866). 



Observations. Under the discussion of the genus Lingula, attention has 

 been directed to the peculiarities of the cardinal area in the type-species, L. 

 anatina, and its close similarity with that of Lingulella Davisi. The necessity 

 of great caution in assigning generic character from these features alone has 

 also been expressed. In Lingula the deltidium bears a broad pedicle-groove, 



