82 COB 



The brain lobes are large, and the ventral commissure enormously 

 thick. The well developed cerebral sense organs abut closely against 

 the posterior ends of the dorsal ganglia. Their ciliated canals pass 

 obliquely inward from the posterior ends of the cephalic slits. In their 

 course these canals pass external and ventral to the dorsal ganglia. The 

 median dorsal nerve, lying just outside the circular muscular layer of 

 the body, is large and conspicuous throughout nearly the whole length 

 of the animal. 



Ocelli are wanting in the adult worm. 



In specimens collected in June and July the genital products had 

 evidently been recently discharged. 



This species is named in honor of Dr. T. H. Montgomery, Jr., of 

 the University of Pennsylvania, whose studies on the Nemerteans form 

 most valuable contributions to the knowledge of the group. 



Habitat. This magnificent Nemertean was found abundantly under 

 stones in muddy places near low water mark at most of the collecting 

 stations between Sitka and Unalaska. At Orca and Virgin Bay, in 

 Prince William Sound, and at Dutch Harbor, Unalaska, it proved to 

 be one of the commonest species. Professor Kincaid has sent me a 

 large specimen from Puget Sound, in the State of Washington, where 

 it is said to be not uncommon. This would indicate that the species 

 may be found locally along the whole northwestern coast of North 

 America south of Bering Sea. 



32. CEREBRATULUS ALBIFRONS sp. nov. 

 pi. iv, figs. 3, 4. 



Body elongated, ribbon-like, flattened behind, rounded in front as in 

 typical species of the genus. Margins of intestinal region pale and 

 thin. Cephalic slits unusually long and deep, reaching well beyond 

 posterior end of mouth. 



Color. General color of body brownish purple. Anterior end of 

 head white, including both dorsal and ventral surfaces, and extending 

 backward about as far as anterior end of mouth, and sometimes reach- 

 ing along borders of cephalic slits to their ends. The esophagal re- 

 gion is dark smoky purple on dorsal surface ; the ventral surface is 

 similar but paler ; the intestinal region inclines more to reddish. A 

 darker line runs along the middle of the dorsal surface and the in- 

 testinal lobes appear more opaque. 



Habitat. Only a single specimen of this pretty species was se- 

 cured, and this, unfortunately, had its posterior extremity missing. 

 The specimen was about 150 mm. in length and of moderate propor- 



