/ 1. Eill-mark (after Williamson). 2. Trail made by a seaweed 

 Ragged along a soft plaster of Paris surface (after Nathorst) VZT, 

 made by Gomada nu^culata, a Polychaet (after Nathorst) 4 Burrow 

 of an msect. ia. Section of the gallery (after ZeiUer) 



