Sunday, September 20, 2020

Ammonites opalus nomen oblitum Fossil Video


Today while researching a fossil I found, I came across a video from the The Society for the Preservation of Natural History Collections (SPNHC). It was created June 12, 2020 for the Specimen Spotlight Friday presentation. The video was entitled "What's in a Name? David Dale Owens' Ammonites opalus nomen oblitum" by Paul S. Meyer of the The Field Museum. Since I recently returned from a visit to that museum and earlier in the year I was at New Harmony, Indiana USA where David Dale Owen lived I thought this would be a good topic to blog about.

Above is an enhanced image of the original illustration from Table VIII Figure 6 of the Ammonites opalus described in Illustrations to the Geological Report of Wisconsin, Iowa, and Minnesota by David Dale Owen Philadelphia: Lippincott, Grambo & Co. 1852. It is described as from the Cretaceous Formation of Nebraska Great Bend of the Missouri River, associated with Inoceramus Cripsii. Below is pattern on the shell.

Paul talks about the type specimen at The Field Museum (FMNH UC 6377) which is now called Rhaeboceras halli. John Evans a forward guide for the Owens survey expedition collected this specimen in 1849 which Owen described in 1852. The link to this video is at

A scan of David Dale Owen's survey report can be found at: