8 PALAEONTOLOGY OF NEW YORK. ■ 



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

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

 fossilization, will frequently exaggerate the normal extension of the umbonal 

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

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

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

 field,t L. Norwoodi,X 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 Chtietopod Annelids. (See accompany- 

 ing figure o[ Lingula pyramidata,\ Stimpson, after Morse, 

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

 action of the sliding or iransmedian muscles in swinging 

 the valves laterally asunder.) no. 3. uiioid,nGiottma)Andebarti. 



After MOKSE. 



* Lingulella loicejisis, Whitfield, Geol. Wisconsin, vol. iv, i>. 242. 1883. 



t Mr. S. A. Mii.i.ER, in his " Catalogue of the Fo.ssil.s foumi in th(! Hudson Rivei', Utica Slate and Trenton 

 Groups, as exposed in the South-ea.'st part of Indiana, Sonth-we.st part, of Ohio, and Noi-lhem p.-irt of Ken- 

 tucky"; Tenth Ann. Kept. Geol. Surv. Indiana, says, on page 19, under the heading Lingula : " All the 

 species referred to this {;enus" [in the groups mentioned] "Leiong to LmgnleUa ; " and in Mr. J. F. Jamks' 

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

 cepting L. Conngtonensi.s), L. attenuala, SmverUy. and f,. i-iciiiifiiriiiin. Hall, are refei-i-ed to the xuh-ije-iiiis 



Ll.MiCLELLA. 



■ t 'ITiis species belongs to the genus Linoitlops. 



§ Cflottidia Audtbarti, Broderip. Davidso.n, Ti-;uis. Linnoan Society, Scicond Ser., Zoology, vol. iv. )iart 

 3. p. 223. 



