354 Mary E. Ckavens aiul Harold Heath, 



CoE (1905) believes that Hydlonemertcs and PeJagonemerfes are rather 

 intimately allied with Nectonemertes and this statement must likewise 

 include PlanMonemertes if we ag-ree with ^Voodworth (1899) that 

 it with Pclagonemertes constitutes a single family {Pelacjonemeriidae). 

 BtJRGER (1895) writes „Ich glaube, die Zeit wird lehren, daß Pela- 

 gonemertes und PlanMonemertes trotz ihrer äußerlichen Ähnlichkeit 

 nicht nälier miteinander verwandt sind" and in the geneological tree 

 on p. 478 Pelagonemertes, owing to the absence of a dorsal vessel, is 

 considered to have early branched off from the hoplonemertean stem, 

 while PlanMonemertes, Nectonemertes and HtjaJonemertes are held to be 

 so fundamentally alike that they with Amphiporns are believed to 

 have had a common ancestor. AVithout considering the possible 

 affinities of the other pelagic nemerteans figuring in this discussion, 

 it appears to us tliat Nectonemertes certainly resembles Ampliiporus 

 in several fundamental particulars and we are inclined with Burger 

 to believe that the two have had a common progenitor. 



Literatureo 



1895. BÜRGER, 0., Nemertinen. m: Fauna Flora Golf Neapel, Monoff. 22. 

 743 p., 3] pi. 



1905. Nemertinen, in: Bronx, K1. Ordu. Tierreich, Vol. 4, Suppl , 

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1905. CoE, AV. E., Nemerteans of the West and Northwest coasts of 

 North xA^merica, in: Bull. Mus. comp. Zool. Harvard Coll., Vol 47, 

 p. 1 — 319, 25 pi. 



1904. JOUBIN, L., Note sur une nouvelle Nénierte pélagique (Necto- 

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1897. Montgomery, Thos. H., Studies on the elements of the central 

 nervous system of the Heteronemertini, in: Journ. Morphol., Vol. 13, 

 p. 381—444, tab. 24—26. 



1901. Thompson, C. B., Zygeupolia litoralis, a new Heteronemertean, 

 in: Proc. Acad. nat. Sc. Philadelphia, p. 657 — 739, tab. 40 — 44. 



1892. Verrill, a. E., The marine Nemerteans of New England and 

 adjacent waters, in: Trans. Connecticut Acad., Vol. 8, p. 382—456, 

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1899. Wood worth, AV. M., Preliminary account of Planktonemertes 

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