PLATE LX. 



Fig. 



1. Head of Syllisarmillaris, 0. F. M. Enlarged. 



2. Head of Ioida macrophthalma, Johnst. Enlarged. 



3. Head of Syllis cucullata, Mel. Enlarged. 



4. Early larva of Autolytus prolifer, 0. P. M., from the sac. X 100. 



5 and ha. Anterior and posterior ends of free bud of Autolytus, St. Andrews, May 25th, 



1885, the former from the ventral surface. Magnified. 



6 and 6a. Dorsal and ventral aspects of the head and proboscis of Nereis pelagica, L. 



Enlarged. 



7 and 7a. Dorsal and ventral views of the head and proboscis of Nereis cultrifera, Grube. 



Enlarged. 



8. Head of Nereis irorata, Mgrn., from the dorsum. Enlarged. 



9. Head and proboscis of Nereis Marionii, Aud. and Ed., from the dorsum. Enlarged. 



10. Proboscis of Nereis Dtimerilii, Aud. and Ed., from the ventral surface (partly 



extruded). Enlarged. 

 10a. Proboscis of the same from the ventral surface (from St. Andrews). Enlarged. 

 106. Head and proboscis in an epitokous form, in which the eyes are much larger than 



usual. Enlarged. 

 10c. Epitokous male from the surface of the sea, Castle Bay, Barra. Enlarged. 



11. Head and proboscis of Nereis diversicolor, 0. F. M. Enlarged. 

 11a. Ventral aspect of the foregoing. Enlarged. 



12. Head of Marphysa Belli, Aud. and Ed. Enlarged. 



