Published in Proceedings of the Biological Society of Washington, in 1920, in volume 33, pages 1-20

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 21-22

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 23-24

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 25-31

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 33-34

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 35-36

Published in Proceedings of the Biological Society of Washington, in 1920, in volume 33, pages 37-40

Published in Proceedings of the Biological Society of Washington, in 1920, in volume 33, pages 41-44

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 45-53

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 55-57

Published in Proceedings of the Biological Society of Washington, in 1920, in volume 33, pages 59-64

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 65-67

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 69-70

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 71-75

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 77-82

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 83-84

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 85-87

Published in Proceedings of the Biological Society of Washington, in 1920, in volume 33, pages 89-90

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 91-92

Published in Proceedings of the Biological Society of Washington, in 1920, in volume 33, pages 93-96

Published in Proc. Biol. Soc. Washington, in 1920, in volume 33, pages 97-100

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 101-102

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 103-106

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 107-111

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 113-115

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 117-120

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 121-126

Published in Proc. Biol. Soc. Washington, in 1920, in volume 33, pages 127

Published in Proceedings of the Biological Society of Washington, in 1920, in volume 33, pages 129-138

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 139-170

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 171-176

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 177-179

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 181-182

Published in Proceedings of The Biological Society of Washington, in 1920, in volume 33, pages 183-185