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List of Nemerteans collected in the Neighbourhood of 

 Plymouth from May-September, 1910. 



By 

 Dr. G-erarda WynliofF. 



With Figure 1 in the Text. 



The following list is one of the results of my work during a stay of 

 nearly four months at the Plymouth Laboratory of the Marine Biological 

 Association. I desire to express my thanks to the Director and the 

 Staff of the Laboratory for the interest they took in my work and for 

 their kind assistance. 



A few of the Nemerteans, recorded in the list of the Ply- 

 mouth Marine Invertebrate Fauna, published in 1904, were not 

 found. For example, Cephalothrix Linearis, which was dredged by Eiches 

 outside the Breakwater, has never been found again, notwithstanding all 

 the trouble taken in searching for it. Amijhiijorus hioculatus, Mcintosh, 

 known from one specimen only from a dredging in Millbay Channel, I 

 have not seen, nor the two new species of the genus Oerstcdia described 

 by Eiches as 0. nigra and 0. immutalilis. To the forms missing in my 

 list I must add Malacohdella grossa, Baseodiscus curtus, Oxypolia beaumon- 

 tiana, Micrella rufa, and Cerehratulus pantheriiius. With the exception 

 of the two Oerstedia species each of the above species has been found in 

 single specimens on rare occasions. Instead of these nine species 

 however, I can add nineteen which have not yet been recorded from 

 Plymouth ; the greater part of these are new to England or the Atlantic 

 Ocean, and four are new species. 



As to the system accepted in this list, I have followed neither Biirger 

 nor Coe. Bergendal's investigations on Carinoma and my own studies on 

 the family Cephalotrichidae resulted in the breaking up of Burger's 

 ordo Mesonemertini. Bergendal's work has revealed many peculiarities 

 in Carinoma, which prove its near relationship to the Tuhulanidae. 

 Moreover certain anatomical features remind us very much of the 

 Heteronemerteans. The Cejphalotrichidae are quite typical Protonenier- 

 teans. but do not possess any character suggesting an intermediate 

 position between the other members of this group and the 3fetanemer- 

 teans. Both genera have therefore been replaced in Biirger's ordo Pro- 

 tonemertini, which means the restoration of Hubrecht's Palaeonemertini. 



Certainly Hctcro- and Palaeonemertini are much more closely related 



