January 28th

1898 – “Capitalsaurus” arrives at the Smithsonian

On this day in dinosaurs, we celebrate Capitalsaurus Day–a commemoration of a mysterious dinosaur without a proper scientific name and which has never been properly described, and yet is honored with the name of a street in the United States capitol.

In 1898, while digging a Washington, D.C. sewer 45 feet below street level, workers discovered a section of a dinosaur backbone and tail. The contractor, J.K. Murphy brought the bones to the Smithsonian on January 28th of that year, and they were sent to Yale a decade later for more precise identification.

Ghosts of DC
Ghosts of DC

Paleontologist Richard Swan Lull determined that the bones belonged to a new species of Creosaurus, which he named Creosaurus potens in 1911. A decade later, the Smithsonian’s Charles W. Gilmore reasoned that the animal might have been Dryptosaurus all along, reclassifying it into a new species he called Dryptosaurus potens.

In the November 27th edition of the Washington Post in 1927, he gave an account of the District of Columbia’s prehistoric fauna:

“One of the bones found in Northeast Washington” he said, “was in a state of almost perfect preservation.  It consists of a single tail vertebra that can be recognized as belonging to one of the huge flesh-eating forms of dinosaur, an animal not less than 30 feet in length.  This monster, when prowling around on its hind legs, would be approximately 15 feet high.  What its presence would mean to a crowd of men and women in the National Capital today may be gauged without much difficulty…Visualize to your heart’s content an area populated with the horrible forms one sees in nightmares, and you will scarcely go wrong in drawing a picture of the District of Columbia during that distant age.”

More than half a century passed without additional discoveries to illuminate the dinosaur’s identity. In the late 1980s, Peter M. Kranz studied the fossil material and concluded it was not sufficiently akin to Dryptosaurus. He began referring to the animal as “Capitalsaurus” (It should be noted that informal names for species or common names for animals, plants, etc. are not italicized).

Even without formal acknowledgement from the scientific community and no official description of the animal, the D.C. Council made Capitalsaurus the District’s official dinosaur in 1998 and proclaimed this day as Capitalsaurus Day in 2001. On January 28, 2000, the block of F Street where the fossil was first unearthed was proclaimed Capitalsaurus Court.

Ghosts of DC
Ghosts of DC

We may never learn more about this mysterious creature, but the next time a building foundation is excavated, or a new sewer line requires trench digging, some lucky worker may find more of Capitalsaurus. Until then, we’ll just enjoy the holiday.

Have you visited Capitalsaurus Court? Share your favorite photos of the street sign or your snapshots with D.C.’s dinosaur displays with us on Facebook and Twitter using the hashtag #TDIDinos.