NO. 13 coe: revision of the nemertean fauna 279 



2. Stylets short, with swollen heads ; basis of central stylet swollen 

 and rounded posteriorly; 11 proboscidial nerves; dark brown 

 above, often with minute purple dots; flesh colored or yellowish 

 white beneath burgeri 



2. Stylets without swollen heads, fluted longitudinally; basis of 

 central stylet not swollen posteriorly; 16 proboscidial nerves; 

 purplish or purplish brown from closely placed mottlings on 

 dorsal surface ; ventral surface gray or yellowish . . purpuratum 



49. Emplectonema burgeri Coe, 1901 



E. violaceum Griffin, 1898 (non E. violaceum Burger) ; E. burgeri Coe, 

 1904, 1905, 1905a. 



Habitat. Among mussels and other growths and beneath stones be- 

 tween tidemarks and below. 



Distribution. Pribilof Islands, Bering Sea, coasts of Alaska and 

 British Columbia, Paget Sound to Monterey Bay, California. 



50. Emplectonema gracile (Johnston) 

 (Plate 30, fig. 40) 



Nemertes gracilis Johnston, 1837; Emplectonema viride Stimpson, 1857; 

 Griffin, 1898; Eunemertes gracilis Burger, 1895; Emplectonema 

 gracile Coe, 1901, 1904, 1905. 



Body. Very long and slender, often twisted and closely knotted, some- 

 what flattened. Body of firm consistency; does not fragment when 

 roughly handled. 



Size. Up to 50 cm or more in length and 2 mm in width; sexually 

 mature when 5-10 cm long. 



Color. Yellowish green to dark green on dorsal surface, pale yellow- 

 ish green or whitish ventrally ; tip of head usually pale or colorless ; entire 

 body gray, creamy white, or pale yellow with tinge of green or pink when 

 young; often pinkish when ova are mature; intestinal diverticula often 

 dark brown. Pale individuals usually become tinged with green when 

 placed in formalin. 



Ocelli. Arranged in 2 groups on each side of head; an anterior, mar- 

 ginal row or elongated cluster with usually 10-15 ocelli of varying sizes 

 and a cerebral cluster with about the same number; much fewer when 

 young (Fig. 40). 



