Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 9

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 10

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 38-40

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 44-45

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 48-50

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 63-64

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 64-65

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 132-147

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 148-149

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 198

Published in Proc. Acad. Nat. Sci. Philadelphia, in 1890, in volume 42, pages 199-200

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 201-218

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 219-249

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 278-281

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 341

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 342

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 343-344

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 407-408

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 409

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 419

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 438

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 441-443

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 472-474

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 474-480

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 481-483

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 487-488

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 488

Published in Proceedings of The Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, pages 492-497

Published in Proceedings of the Academy of Natural Sciences of Philadelphia, in 1890, in volume 42, issue 2, pages 192-196

Published in Proceedings of The Academy Philadelphia, in 1890, in volume 1890, pages 284-288

Published in Proc. Acad. nat. Sci. Philad., in 1890, in volume 1890, pages 420-434