MARINE BIOLOGICAL STATION AT PORT ERIN. 77 



Goodsir's " Syntethys " is the same animal as Savigny's 

 " Diazona," but that whereas the animal when living in 

 the Mediterranean is usually violet when alive, the 

 Hebridean form only becomes violet after preservation in 

 alcohol. Professor E-einhard Dohrn, Director of the 

 Zoological Station at Naples, has kindly sent me a pale 

 green Mediterranean specimen, and informs me that both 

 green and violet-coloured specimens have been obtained 



Fig. 20. Violet Hebridean Diazona after preservation in alcohol — less 

 than half natural size. 



from time to time in the neighbourhood of Naples. It 

 has not been noticed at Naples that the green colonies 

 change colour in alcohol. 



The brilliant green solution which my Hebridean 

 specimen has given with alcohol has been examined 



