FREFACE. 



pirliaps help the workers who succeed me to better 

 results thau I have attained. 



It only remains to discharge the pleasant duty of 

 acknowledo-iiio- the various assistance which has been 

 so freely rendered to me. 



To Mr. Busk I am under great obligations for 

 the readiness with which, through many years, he 

 has given me the benefit of his extensive knowledge 

 and large stores of material, and for his friendly 

 sympathy amidst the difficulties incident to my work. 



From the Rev. A. M. Norman I have received in- 

 valuable assistance. His unsurpassed collections, 

 comprising the rich inheritance bequeathed by the 

 late Mr. Barlee, and the fruit of his own extensive 

 dredgings, have been placed unreservedly at my ser- 

 vice. Unique specimens of great value, and the 

 types of the species described by himself, have been 

 freely lent, in spite of all the risks of transit, and have 

 been left in my hands as long as wanted. Many of the 

 figures in this work have been drawn from examples 

 which his kindness has supplied. I also owe to him 

 the opportunity of examining extensive series of speci- 

 mens, such as only a collection like his could supply, 

 thus making a more complete study of the spe- 

 cies than would have been otherwise possible. And, 

 in addition to this material help, most bountifully 

 rendered, I have also to acknowledge much valuable 

 information, especially respecting the distribution of 

 the Polyzoa, which has been freely placed at my dis- 

 posal. The service which Mr. Norman has rendered 

 me has been large in extent and peculiar in kind , 



