coe: nemerteans of west and northwest coasts. 249 



Nephridia remarkably extensive, reaching from brain region back- 

 ward beyond the first few pairs of reproductive glands ; with numer- 

 ous efferent ducts. Usually 5 to 10 efferent nephridial ducts on 

 each side, of which several of the more posterior ones open on 

 dorso-lateral surfaces of body, the others opening ventro-laterally. 



Habitat. — Very abundant among algae between tides and on 

 piles of wharf, Victoria, B. C, and southern Alaska (Coe, : 01) ; Puget 

 Sound, and Sitka, Alaska (Griffin, '98). 



Common also among shells and algae at the breakwater, San 

 Pedro Harbor, C'alifornia. 



This is the most abundant of all species of nemerteans found at 

 Pacific Grove, California, occurring among rocks and algae fully 

 half way from low tide to high-water mark. 



Copper Island (Commander group), Siberia ; collected by Prof. 

 D'Arcy Thompson. These specimens were peculiar in having but 12 

 proboscidial nerves and in having 10 to VI efferent nephridial ducts 

 on each side, all of which opened ventrally (Punnet, :01, p. 95). 



Bei'ing Island (Commander group), Siberia, collected by Dr. L. 

 Stejneger on beach, August, 1897. 



Port Providence, Plover Bay, Siberia (near Bering Strait). Col- 

 lected by E. P. Herendeen, August, 1880. 



The present known range of this very common species is therefore 

 from San Pedro, California, to Puget Soiind, to Alaska, to the 

 Commander Islands off the coast of Kamchatka, to Bering Strait. 

 This range represents an extent of more than 5,000 miles of coast 

 line and extremely different environmental conditions, the water at 

 San Pedro being constantly at a temperature of at least 50-70° F., 

 while that in Bering Strait is covered with pack-ice during a con- 

 siderable portion of the year and is never much above the freezing 

 point. 



59. Amphiporus similis, sp. nov. 



PI. 16, figs. 93, 94; PI. 22, tigs. 152, 153. 



Body small, slender; usually only 8 to 15 mm. in length and less 

 tlian 1 mm. in width. Head rather slender, with two pairs of 

 lateral oblique furrows as usual. 



Color. — White with tinge of pinkish or yellowish ; intestine and 

 intestinal caeca, the latter extending nearly to brain, very pale yellow 

 or slightly brownish. 



