164 BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 



very large efferent ducts situated at about two thirds the distance 

 toward their posterior ends. For further details of anatomical 

 peculiarities, see Coe, : 01 or : 04. 



Habitat. — Common in mud and vinder stones in muddy localities 

 in Prince William Sound, Alaska (Coe, : 01). Also collected by Dr. 

 W. H. Dall under stones, Unga Island, Alaska. These latter speci- 

 mens, although collected 30 years ago, still retain a deep pur])le 

 color, and the white spot on tip of snout can still be distinguished. 



The individuals are hardy and of sluggish movements. They do 

 not break up nor contract excessively when thrown into killing 

 Huid, and the proboscis is not usually everted when the animal is 

 killed. Some, especially the smaller ones, when preserved are nearly 

 cylindrical, but most individuals are flattened ventrally. 



17. Lineus rubescens Coe. 



Harriman Alaska Expedition, 11, p. 179, PL 14, fig. 1 ; PI. 1.5, figs. 



3, 4; PI. 22,%. 1,1904. 



PI. 3, fig. 33. 



This beautifully colored but rather uncommon CaUfornian species 

 may be easily recognized by the following pecvdiarities : — 



Body very slender, rounded anteriorly, flattened in intestinal 

 region ; posterior extremity slender ; head long, rather broad ; 

 cephahc furrows correspondingly long, reaching posteriorly as far as 

 anterior end of mouth, which is situated well back from tip of 

 snout. 



iSize. — A small species, individuals seldom exceeding 10-15 mm. 

 in length and 1 mm. in diameter. 



Color. — Anterior portions of body, except tip of head, pink or 

 rosy flesh color; sometimes blight pinkish red, and often with 

 bluish tinge. Anterior end of head, both above and below, white, 

 sharply marked off from pink color behind (PI. 3, fig. 33). Intes- 

 tinal region varies fi'om deep flesh color to pale purplish brown 

 anteriorly, shading off to very pale pinkish toward posterior end of 

 body. Ventral surface paler, but of similar color, often with still 

 paler median line. Intestinal lobes flesh color, buff, or occasionally, 

 brownish or purplish. Plead can be so much contracted that white 

 tip will disappear. 



