232 THE GENERA OF NEMERTEANS. 



monograph on the same subject, in which I will be enabled, 

 through the liberal succour of the energetic foundator of 

 the zoological station at Naples, Prof. Anton Dohrn, to give 

 coloured figures of the different species and numerous il- 

 lustrations of anatomical details. The splendid example 

 given by the Ray Society in pubHshing Dr. Mac Intosh's 

 coloured figures of Nemerteans has at the same time shown 

 how it is possible only in this way to avoid and gradually 

 to clear away the endless confusion which has hitherto pre- 

 vailed in the definition and nomenclature of these worms, 

 which are so difficult to recognize by external features. 

 Mac Intosh himself has contributed considerably to clear 

 up this confusion by his extensive knowledge of the Ute- 

 rature of the subject and by his careful and exhausting 

 treatment of the synonymy. Jensen's figures too are very 

 fair and henceforth it will be necessary to figure every 

 species that is described as new. 



Finally I subjoin a list of those European species which 

 I regard as well characterized but which 1 did not obtain 

 from the Bay of Naples. They are: 



Prosorliochmus claparedu Kef. , Tetrastemma kefersteini 

 (Mar.) Hubr. , Tetrastemma hermaphroditica (Kef.) Hubr. , 

 Linens longissimus (Gunn.) Sow. , Linens ohscurus Desor , 

 Amphiporus splendidus (Kef.) Barr., Nemertes carcinophila Köll. 



With the fifty species mentioned in the foregoing pages 

 this makes the total of European species of Nemerteans 

 amount to fifty-seven. 



For certain contributions to the anatomy of the group 

 I refer to a preliminary account in the «Zoologischer An- 

 zeiger, 8 Sept. 1879» which will ere long be followed by a 

 more elaborate account of the investigations I had occasion 

 to make during my stay at Naples. 



Notes frona the Leyden Museum. 



