My current theory is that is not a fossil fish at all but a metal artist's creation. It appears to be be a cross between a carp (the body) and a herring (the fins) thus some sort chimera.
While researching it some more, I came across some 1934 historic American buildings survey images in the Library of Congress of New Harmony, Indiana, USA. They show the top of the conical roof with just a metal blastoid fossil. The Archimedes bryozoan screw fossil and fish are missing. So maybe the top was added later thus the fish was not significant. See orange arrow in image below.
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| Historic American Buildings Survey, C. & Rapp, G. (1933) Dr. David Dale Owen House, Church Street State Highway 66, New Harmony, Posey County, IN.
Indiana New Harmony Posey County, 1933. Documentation Compiled After.
[Photograph] Retrieved from the Library of Congress,
https://www.loc.gov/item/in0163/. Photographer Homer Fauntleroy April 7, 1934 |
Also the house has a little trilobite pattern at the top of some outside windows and doors. See the yellow arrows in the picture above and below.
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Historic American Buildings Survey, C. & Rapp, G. (1933) Dr. David Dale Owen House, Church Street State Highway 66, New Harmony, Posey County, IN. Indiana New Harmony Posey County, 1933. Documentation Compiled After. [Photograph] Retrieved from the Library of Congress,https://www.loc.gov/item/in0163/. Photographer Homer Fauntleroy April 7, 1934
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The idea that the upper two fossils representations were added later after its 1859 completion was dashed by the entry in a book written by David Dale Owen's granddaughter,
Caroline Dale Snedeker née Parke (March 3, 1871 – January 22, 1956). She gained some fame for writing fictional books for young people in the early 1900s.
One non-fiction book she wrote about New Harmony from stories told to her by her grandmother. It was called The Town of the Fearless and published in 1931. On page 348 she writes, "Also here is the New Laboratory, a charming building in English nineteenth-century style, which David Dale Owen built, and upon which he expended his artistic skill and loving fancy. On the spire of its little tower swings a geological fish as weather vane. Over its door is carved a trilobite. All this is in one plot of ground which is now a beautiful grove and a bird sanctuary."
So when the photos were taken in 1934 the weather vane must have been under repair. Of course, maybe the fish was changed out after being there for over 90 years.
The house has also been profiled by the Society of Architectural Historians at this page:
