1^03] On the Nemerteans of Norway. 7 



Page 



7. Linens scandinaviensis n. sp. Medium sized form. Cutis 



feeble. Cephalic vascular lacuna. Head slits faiiiy 

 deep but not past cerebral organ. Proboscis 2 layered 

 with crosses. Rhynchocoelom not to posterior end. No 

 frontal organ or eyes. Several excretory ducts on 

 either side 16 



8. Linens einerens n. sp. Medium sized form. Cutis fairly 



well developed. Irregular cephalic vascular lacuna. 

 Head slits do not reach past cerebral organ. Rhyncho- 

 coelom not to posterior end. Proboscis two-layered 

 with muscle crosses. Eyes and frontal organ present. 

 Excretory system with several ducts 17 



9. Linens longissimus (Gunnerus, 1770) 19 



10. Linens bilineatus (Mc Intosh, 1873) 19 



11. Micrura varicoJor n. sp. §mall species of variable colour. 



Caudicle present. Cutis fairly well developed. Cephalic 

 vascular lacuna. Head slits do not reach past cerebral 

 organ. Rhynchocoelom to posterior end. Proboscis 

 two layered with muscle crosses. No eyes. Frontal 

 organ. Excretory system with several ducts 19 



12. Micrura atra n. sp. Medium sized form of dark grey 



colour. Caudicle present. Cutis feeble. Cephalic vas- 

 cular lacuna. Head slits just past cerebral organ. No 

 eyes. Proboscis two layered with muscle crosses. Rhyn- 

 chocoelom not to posterior end. Several excretory ducts 21 



13. Micrura bergenicola n. sp. Small red brown form. Cutis 



feeble. Cephalic vascular lacuna. Head slits not past 

 cerebral organ. No eyes. Frontal organ. Proboscis 

 two-layered with muscle crosses. Rhynchocoelom to 

 posterior end. 1 pair of excretory ducts 22 



14. Micrura purpurea (Dalyell, 1853) 24 



15. Micrura fasciolata (Eheenbebg, 1831) 24 



16. Cerebratulus norvegicus n. sp. Large form with well 



marked side folds. Colour light grey brown. Caudicle 

 present. Cutis feeble. Cephalic vascular lacuna. Head 

 slits, as a rule, not past cerebral organ. No eyes. 

 Frontal organ. Rhynchocoelom to posterior end. Pro- 

 boscis 3 layered with muscle crosses. Single excretory 

 duct on either side 24 



17. Cerebratulus longifissus (Hubeecht, 1887) 26 



