<> 



PREFACE. 



The following fasciculus may be described as the First Part of a Monograph of the 

 British Annelida, a department of native Zoology which more than any other required investi- 

 gation, and whose neglected condition formed the author's chief inducement to attempt something 

 for its improvement. 



So little was known in this country with respect to the Nemerteans, while their structure 

 and zoological affinities opened up so many interesting questions, that they could scarcely be 

 passed over in such a treatise. Accordingly they have been examined — both in the living and 

 preserved conditions — with as much care as the circumstances of the author admitted. He hopes, 

 moreover, that the publication of the skilful and laborious coloured drawings of the external 

 configuration of these worms (which were so kindly executed by her to whom the work is 

 dedicated) will assist in rescuing them from the comparative obscurity in which they have 

 hitherto been involved in this respect, both in Britain and on the Continent. He has 

 endeavoured to render the other parts of the treatise worthy of the delicacy and beauty of these 

 figures. 



The species of the group are, on the whole, distinctly marked, so that comparatively little 

 difficulty has been experienced in discriminating them ; indeed, the chief variation in the majority 

 is in colour, which, of coarse, obscures none of the essential characteristics. 



Considerable additions may be expected to the list of species subsequently described 

 (though the dredge has been used and the coast-line minutely examined at many points from 

 the Shetland to the Channel Islands), and not a little new matter in regard to anatomy and 

 development ; but, with such a field as the whole Annelida before him, the author could not 

 devote more time to the group. As no freshwater species has yet been found in this country, 

 such a habitat especially should be diligently explored. The author, however, will be satisfied if 

 he has paved the way for a more extensive and accurate study of these beautiful and interesting 

 forms, whose life-histories and structure so amply reward investigation. 



The Nemerteans have received so little attention from British zoologists that the author's 

 list of contributions in this respect cannot but be small, and it is solely to the ceaseless care of a 

 friend that he has been enabled to pursue the investigation with that completeness necessary for 

 the elucidation of their anatomy and zoology, an investigation demanding an abundant and ever- 

 ready supply of healthy living animals. Mr. Parfitt forwarded a few living specimens from the 

 Devonshire coast, and Dr. Howden of Montrose, Prof. E. P. Wright of Dublin, Dr. Gray, 



