184 COE 



18. LINEUS FLAVESCENS sp. nov. 

 p1. xvii, figs. 3, 4. 



Body of moderate proportions for the genus ; head long and rather 

 slender, usually a little narrower than body, often pointed, and often 

 slightly emarginate in front ; cephalic slits longer than in most related 

 species ; esophageal region rounded ; intestinal region only moderately 

 flattened ; posterior extremity rather slender, without caudal cirrus ; 

 proboscis sheath extends nearly to posterior end of body ; proboscis 

 rather slender. 



Color. — General color of body yellowish, but of a great variety of 

 shades in different portions of the body, and in different individuals. 

 A number of specimens from crevices of rocks at San Pedro Harbor 

 were pale yellow, sometimes with a tinge of orange, in esophageal 

 region, and deep ochre throughout the remainder of the body except 

 the head, which was ochre with a decided tinge of orange. Margins 

 of head are paler. The pale yellow of esophageal region changes 

 abruptly to the ochre of the intestinal region ; posterior extremity and 

 whole ventral surface of body of a duller, paler color. 



Esophageal region often shows two distinct regions of different color, 

 due to the two divisions of the esophagus described below. The 

 anterior pear-shaped region lying next the mouth is more deeply 

 colored, corresponding with the thicker esophageal walls, while the 

 remainder of the region is usually paler (p1. xvii, fig, 4). 



Several specimens from among annelid tubes on San Pedro break- 

 water were deep ochre anteriorly, with a sharp, median, dorsal, longi- 

 tudinal white line which extended through the anterior half of the 

 esophageal region. The remaining portion of esophageal region was 

 greenish ochre, while the whole intestinal region was dull orange (due 

 largely to the color of the intestinal canal), covered superficially by the 

 pale yellowish of the body walls. Ventrally the color was dull whitish 

 on head and in anterior esophageal region, then greenish ochre back as 

 far as the intestinal region, which was of the same orange color as dor- 

 sal surface, but somewhat duller. Lateral and anterior margins of 

 head colorless ; cephalic slits long, sharply separating the ochre or 

 yellowish orange of dorsal surface from whitish of ventral surface of 

 head. Smaller specimens were commonly much paler in color. Some 

 individuals were of duller colors, with dark buff Intestinal regions. 



Numerous large individuals taken in from 50-100 fathoms between 

 San Pedro and Santa Catallna Island were of a rich golden brown 

 anteriorly, with a tinge of yellowish orange on the head. Intestinal 



