Lingula corbourgensis brachiopod from the Whitby formation

The most common Brachiopod to be found in the Collingswood member of the Whitby formation is Lingula corbourgensis. It is an inarticulate Brachiopod with a phosphatic shell and can get relatively large. Below are several examples that occur on slabs that I've split.

Specimen #1

Specimen #2

Specimen #3

The Whitby formation is Ordovician in age (late Ordovician, Katian/Mohawkian stage).
These fossils were collected from the St. Mary's Limestone Quarry in Bowmanville, Ontario. I used William Hessin's book "South Central Ontario Fossils", 2009, Self Published, pg. 117 to help identify these fossils.