This paper discusses and illustrates 17 species of ostracodes from the uppermost part of the Leonard formation or lowermost part of the Word formation and 1 species from the Wolfcamp and Leonard formations in the Glass Mountains, Texas. Also, 1 species from the Pennsylvanian of Oklahoma is illustrated for comparison. Thirteen of these species are new, and 1 unnamed. These are distributed in the following 14 genera, 5 of which are new: Bairdia? McCoy, Ceratobairdia, n. gen., Kirkbya Jones, Coronakirkbya, n. gen., Knightina Kellett, Amphissites Girty, Polytylites Cooper, Kellettina Swartz, Semipetasus, n. gen., Kindlella, n. gen., Miltonella Sohn, Sanniolus, n. gen., Coryellina Bradfield, Roundyella Bradfield.
The Kellettininae, a new subfamily of the Kirkbyidae, is proposed. The genus Kirkbya is revised and as a result of this revision, is now restricted in known stratigraphic range to Paleozoic rocks younger than the Devonian.
The morphology of the marginal rims in Kirkbyidae is studied by means of serial polished surfaces.