Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1909, in volume 60, pages 586-599

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 2

Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 3-54

Published in Proceedings of the Academy of Natural Sciences of Philadelphia (Proc. Acad. Nat. Sci. Philad.), in 1909, in volume 61, pages 111-175

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 176

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 193

Published in Proc. Acad. nat. Sci. Philad., in 1909, in volume 61, pages 194-234

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 298

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 321-351

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 367-368

Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 406-408

Published in Proceedings of the Academy of Natural Sciences, Philadelphia, in 1909, in volume 61, pages 409-483

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 572-573

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1909, in volume 61, pages 586-587