Reprinted from the Quarterly Journal of Microscopical Science, 



April, 1S9J. 



CONTRIBUTIONS TO A KNOWLEDGE OF BRITISH 

 MARINE TURBELLARIA. 



By F. W. Gamble, B.Sc, Berkeley Fellow of Owens College, Manchester. 



With Plates X, XI, <fc XII. 



Contents. 



I. Introductory. 



1 . Nature and scope of the paper. 



2. Historical account. 



3. Nomenclature. 

 IL Systematic. 



Rhabdoccelida. 



Tricladida. 



Polycladida. 



III. Summary. 



IV. Appendix. 



Key for determination of families, 

 sub -families, genera, and 

 species of British marine 

 Turbellaria. 



V. Literature. 



I. Introductory. 



1. Nature and Scope of the Paper. 



It is usual to begin a fauuistic paper on Turbellaria with the words 

 of Oscar Schmidt, ' ; Man braucht, wie es scheint, wo man will nur 

 zuzugreifen und ist der Ausbeute sicher ;" and although written forty 

 years ago, they are still applicable to this group. In the northern 

 European seas (and it was to these that Schmidt referred) many 

 species may be found by careful examination of almost any portion of 

 the littoral aud laminarian zones. Yet, owing probably to their small 

 size, inconspicuous appearance, perishable nature, and obscure anatomy, 

 few naturalists in this country have devoted much attention to them. 

 When once a keen interest, however, is aroused, the number of new 

 and morphologically important forms that may be found in a limited 

 area is beyond anticipation. This has been well expressed by Jensen 

 in the preface to his work on the Turbellaria of the west coast of 

 Norway : " The new forms described here are only a very small part 



