12 Stewart, Bra?ichial Lamellae of Ligia oceanica. 



Plate II. 



Fig. I. — T.S. of the gill of a specimen kept for one week in 

 sea-water. 



a = endopodite, ^ = exopodite. 



Fig. 2. — T.S. endopodite of the same gill, magnified by Zeiss 

 objective \. 



Fig. 3. — T.S. of the gill of a specimen kept for eight hours in 

 fresh water. 



a = endopodite, ^ = exopodite, f= peduncle, x = point 

 at which the gill is first affected. 



Fig. 4. — T.S. endopodite of same gill, magnified by Zeiss 

 objective \. 



