PREFACE. 



produce some of the admirable figures from his great 

 work on Polyzoan Embryology, and also communica- 

 ting to me some of the latest results of his researches 

 a service for which my warmest acknowledgments 

 are due. 



I certainly have reason for holding that good fel- 

 lowship and an unselfish devotion to the interests of 

 science are still the prevalent characteristics of the 

 naturalist. May they be perpetual ! 



In the preparation of this work I have had the 

 cordial cooperation of the Publisher, to whom British 

 Natural History owes so much, and who is still true 

 to the honourable traditions of his house. 



The Plates bear witness to Mr. Rollick's admirable 

 accuracy, and to his power of rendering the minutest 

 detail with perfect fidelity. It is also right that 

 Mr. Evans and Mr. Kirchner should have the credit 

 of the Woodcuts, which do justice to their subjects. 



In closing the pleasant labour of many years, I 

 may take up the lament of that fine old student of 

 nature, Otho Fabricius, " non sine dolor e multa intacta 

 relinquere coactus fui; " and (under a full sense of the 

 imperfections of my work, beyond its mere incom- 

 pleteness) I add, with him, " unico illo solatia fref/t*, 



QUOD .ETAS SUPPLERET DEFICIENTIA." 



T. H. 



Budleigh-Salterton, Devon, 

 November 1879. 



