No. 4. MAY, 1911 



John U'aukkx. Tlic (icvclopincnt of the paraphysis and pineal region in 



Kept ilia. Thirteen plates 313 



John Lewis Bremer. Morphology of the tubules of the human testis and 



epididymis. Twelve figures 393 



Charles Russell B.\hdeen. Further studies on the variation in suscepti- 

 bility of amphibian ova to the X-rays at different stages of develop- 

 ment. Eighteen figures 419 



