5. HEREDITY OF HAIR-LENGTH IN GUINEA-PIGS 



AND ITS BEARING ON THE THEORY 



OF PURE GAMETES 



BY 



W. E. CASTLE AND ALEXANDER FORBES 



6. THE ORIGIN OF A POLYDACTYLOUS RACE 



OF GUINEA-PIGS 



BY 



W. E. CASTLE 



PUBLISHED BY THE CARNEGIE INSTITUTION OF WASHINGTON 



MAY, 1906 



