Saturday, May 1, 2021

Onychochilus nitidulus Gastropod Fossil


Here is an image drawn by Elvira Wood in 1901 which she used to show fossil gastropod called Onychochilus (?) nitidulus (Clarke, 1894). She described and illustrated it in the 1901 paper Marcellus (Stafford) Limestones of Lancaster, Erie Co. N.Y. on pages 190. Illustration on plate 9 figure 20. Described as "A small exfoliated specimen."

On page 170, listed as "In bed III is found a minute sinistrally coiled gastropod which corresponds with Clark's description and figures except that, instead of a faint carination of the whorls, there is a distinct spiral band. The concentric growth lines are interrupted in passing over this band, which is apparently partially filled by foreign matter. This feature is well shown on the body whorls of one specimen only, but, if the  discovery of other specimens confirm this observation, they should be referred to the genus Hesperiella of Holzapfel rather than Onychochilus, with which I have doubtfully placed my specimens."