76 



of being furuishetl with a large pouch, cap.ihle of holding about IJ ounces of 

 fluid, on its ventral surface immediately behind the mouth, and extending as 

 far backwards as the second gill opening. The parieties of the sac were alto- 

 getlier membranous and cutaneous, no trace of muscular fibre could be 

 detected, nor could any opening into the gullet or elsewhere be discovered. 

 It may possibly act in the same manner as the swinuning bladder of other fish, 

 which is absent in the Lampreys, but as additional specimens are expected 

 from the same locality it is intended to have a more minute dissection befcjre 

 forming any positive opinion on the subject. 

 The proceedings were closed by the usual vote of thanks. 



