PLATE VI. 



Fig. I. Cerebratulus monigomeryi^^. no\. Dutch Harbor, Unalaska. Natural 

 size. 



2. Head of same species from ventral surface. 



3. Cerebratnlus occidentalis sp. nov. Yakutat. Natural size. 



4. Amphiforus angulatus [Y2ihx.)\Qrr\\\. Kadiak. Natural size of large 

 specimen. 



(96) 



