8 



PALEONTOLOGY OF NEW YORK. 



is not to be confounded with the deep pedicle-slit in Lingui.ella. Furthermore, 

 a slight longitudinal displacement of the valves before, or while undergoing 

 fossilization, will frequently exaggerate the normal extension of the ural)ona] 

 region in the pedicle-valve, beyond that in the opposite valve. We are dis- 

 posed to consider the current reference to Lixgolella of several well-known 

 American species, e. g., L. lowensis, Owen,* L. Covingtonensis, Hall and Whit- 

 field,! L. Norwoodi,! James, L. Vanhornii, Miller, as incautious, and feel that, 

 in general, these are more safely left under the original genus. Two of the 

 species named, viz., L. lowensis -and L. Vanhornii, 

 have muscular impressions comparable with those 

 of L. anatina, and of widely different character and 

 arrangement from those in the genus Lingulella, 

 Living Lingulas, are known to form a tube about the 

 pedicle by the agglutination of grains of sand or other 

 sedimentary debris, after the manner of Tubifex and 

 other forms of Chaetopod Annelids. (See accompany- 

 ing figure o( Lingula pyramidata,^ Stimpson, after Morse, 

 which shows this tube, as well as the efiect of the 

 action of the sliding or transmedian muscles in swinging 

 the valves laterally asunder.) fig. 3. jjnguia(Giottidia)An(iebarti. 



After Morse. 



* Livgulella lowensis, Whitfield, Geol. Wisconsin, vol. iv, p. 242. 1883. 



t Mr. S. A. MrLLER, in his "Catalogue of the Fossils found in the Hudson River, Utica Slate and Trenton 

 Groups, as e\i)osed in the South-east part of Indiana, South-west part, of Ohio, and Northern pwrt of Ken- 

 tucky"; Tenth Ann. Kept. Geol. Surv. Indiana, says, on page lil, under the heading Linghla : " All the 

 species referred to this fjenus " [in the groups mentioned] " l)elong to Livgulella; " and in Mr. J. F. James' 

 "Catalogue of the Fossils of the Cincinnati group," 1881, in addition to the species mentioned above (ex- 

 ccjiting X. C(rvinglonensis), L. attenuata, Sowerby, and L. riciniformis. Hall, aie referred to \\\g svXi-geims 



Ll.VliULELLA. 



\ ITiis species belongs to the genus Lingdlops. 



§ (flottidia Audfbarti. Broderiji. Davidson, Trans. Liiuiean Society, Second Ser., Zoology, \ol. iv, jiart 

 3, p. 223. 



