NO. 13 coe: revision of the nemertean fauna 283 



PLATE 24 



Fig. 1. Euborlasia nigrocincta. Light-colored variety with conspicu- 

 ous bands. Regenerating posterior extremity. 



Fig. 2. E. nigrocincta. Dark variety, with inconspicuous bands. 



Fig. 3. {a) Neviertopsis gracilis, with dorsal stripes separated ante- 

 riorly. (/>) A^. gracilis var. bullocki, with dorsal stripes 

 united anteriorly by broad transverse band. 



Fig. 4. Lineus atrocaeruleus. Anterior end of body. 



Fig. 5. Tetrastemma sexlineatum. (To the left of Fig. 6.) Dorsal 

 surface with portion of ventral surface bordered by the nar- 

 row marginal stripes. 



Fig. 6. T. sexlineatum. Anterior end of body; flattened to show the 

 six longitudinal stripes. 



Fig. 7. Cerebratulus californiensis. Dark red variety. 



Figs. 8-10. C. californiensis. Anterior portions of bodies of light and 

 dark varieties and dark variety with pale margins, respec- 

 tively. 



Fig. 11. C. californiensis. Very young individual with light-colored 

 body and deeply pigmented head. 



Fig. 12. Micrura alaskensis. Deeply colored, sexually unripe indi- 

 vidual. 



