Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1868, in volume 19, pages 166-211

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 1

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 2-81

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 85-86

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 87-91

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 91

Published in Proc. Acad. Nat. Sci. Philadelphia, in 1868, in volume 20, pages 96-140

Published in Proc. Acad. Nat. Sci. Philadelphia, in 1868, in volume 20, pages 138-139

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 145-146

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 153-156

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 156

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 159

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 160-161

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 177

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 178-180

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 182-183

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 196-197

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 205-208

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 208-221

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 221-227

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 227-228

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 229-230

Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 305-313

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 313-314

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 314-315

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 315-316

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 334

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 359-430

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 373-382

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 394-396

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1868, in volume 20, pages 400-419