NOTE OX THE ILLUSTRATIONS. 



As many species described in the present volume were not 

 fig-tired by the nnthors, including nearly all those originally 

 described by Milne Edwards in his beautifully illustrated 

 monograph/ Observations surles Ascidies composees des cotes 

 de la Manche/ the Editor considered it advisable to add 

 largely to the illustrations from that and other sources. 

 With this view all the coloured figures in Edwards' mono- 

 graph which represent British species were photographed, 

 and are hei'e reproduced, mostly in colour, with a few of his 

 uncolonred figures, and also several from Savigny's classical 

 work, ' Memoires sur les Animaux sans Vertebres.' 



In addition to these, the earliest published figures of every 

 other species included in the volume are reproduced, also by 

 photography, as text-figures. 



By this means, the volume, instead of being by far the most 

 meagrely illustrated of the three, as it would otherwise have 

 been, is, for its extent, the most richly illustrated. 



All the illustrations have been executed by Andre & Sleigh, 

 Ltd., of Bushey, Watford. 



J. H. 



