1900-1901.] Prof. Letts and Mr Hawthorne on Tllva latissima. 295 
EXPLANATION OF PLATES. 
Plate 1. 
Young plants of Ulva latissima with root attachment as they 
appear when pressed. 
Plate 2. 
Diagram to illustrate the occurrence of Ulva latissima in 
Belfast Lough. 
The light shading indicates the shore or hanks uncovered at low 
water. 
The dark shading indicates those parts of the shore or hanks 
uncovered at low water where the ulva abounds. The arrows 
indicate the distribution of sewage on the ebb and flood tides. 
Plate 3. 
Diagram to illustrate the occurrence of Ulva latissima in 
Dublin Bay. 
The light shading indicates the shore or banks uncovered at low 
water. 
The dark shading indicates those parts of the shore or banks 
uncovered at low water where the ulva abounds. 
