102 Mr H. Goodsir on the Sexes of the Cirripeds, S^c. 



of the two pairs of spined extremities. The tail is also in 



constant motion. 



SECTION IV. ON THE MATDRE OF THE FISHERMEN. 



Hearing our fishermen often speak of " something'' which 

 abounded in great quantities in the Firth of Forth during the 

 summer months, which they called Maidre^ and of which they 

 never could give me a clear description, I determined to exa- 

 mine it for myself. 



It was stated to me that this maidre was generally found in 

 greatest quantity round the Island of May, only during the 

 summer months, and especially during the time of the herring- 

 fishing. 



I find, however, that maidre must abound during the spring 

 months also, as the stomachs of the herrings caught at present 

 are in most cases filled with it. 



In frequent excursions to the Isle of May, during last year, 

 I found that the maidre consisted of one immense continuous 

 body of minute animals. 



The animals composing this immense body were those be- 

 longing to the Cirripeds, Crustaceans, and Acalepha. 



Of these the Crustaceans existed in the greatest numbers, 

 or rather masses, for it gives a faint idea to speak of numbers. 

 The Crustacea were Amphipoda and Entomostraca, the for- 

 mer of which were very abundant, but the latter (Entomos- 

 traca) formed the greatest proportion of this innumerable body 

 of animals. 



The Acalepha also abounded, of which the different species 

 of Berooe were seen in greatest numbers. 



I remarked that the masses of maidre abounded most at 

 the sheltered sides of the island. On looking into the water, 

 it was found to be quite obscured by the moving masses of 

 Entomostraca, which rendered it impossible to see anything, 

 even a few inches below the surface. 



But if, by chance, a clear spot is obtained, so as to allow 

 the observer to get a view of the bottom, immense shoals of 

 coal-fish arc seen swimming lazily about and devouring their 

 minute prey in great quantities. Occasionally small bhoals 

 of herrings are seen pursuing them with greater agility. It is 



