of the Fishery Board for Scotland. 



255 



Fig. 87. 

 88. 

 89. 

 90. 

 91. 

 92. 

 93. 



94. 

 95. 

 96. 

 97. 

 98. 



99. 



30. 



Drawing (natural size) of a mussel that had grown in the pond at 



Bay of Nigg. July 20, 1907. View from above. 

 Diagrammatic median section of the bjssus-pit. 

 Side view of mussel shown in fig. 93. 

 Drawing of excretum of mussel. 



,, ,, ,, section. 



Drawing showing the cloud formed in tank by the discharge of sperms 



by two examples of the horse-mussel (Modiolus modiolvs\ 

 Transplanted mussel. (St. Andrews.) A-B is the size of the original 



seed ; B-C is the increase after transplanting. 



