SPECIAL PART 



THE liisl Kchinodenn larvtv (lescribed were designated, more or less 

 consistently, by binominal names — liipinnai in dslcrificrd Sars, 

 Pluleiis paradoxus Job. Miiller, Plulciis bimarulalus Job. Miillor. II 



is true, they were partly not ie(_OjL>nize(l as Kcbinoderm larva*; but this 

 does not alter tbe fact Ibal Ibesc larva' got binominal names. In the 

 author's work on the Kchinoderm larva of the Plankton Expedition this 

 j)rinciple was carried through consistently lor all b",chinoderm larva" 

 known lill IIumi, in view of liu' necessily of having the dilTerenl larval 

 forms designated in such a way thai we may understand without loo 

 much trouble what we are speaking of. This recpiesL is met in a satisfactory 

 way by the binominal nomenclature, bul nol by such designations as 

 "Auricularia mit Kugeln", "liipinnaria aus llelsingor" or Ihe like, used 

 so often in the elder litterature (.loh. Miiller, Metschnikof f). For 

 larvae of known origin no special larval name was created, wiiich was, 

 of course, unnecessary. This way of naming the larva has been generally 

 adopted by the few authors who have since then described lu'hinoderm 

 larva of unknown parentage (MacHride, demmill). 



In the present work the same method is also adopted, bul modified 

 to some extent. On account of the great number of new larval forms 

 of unknown origin described here, especially ol Ophiurids, it was felt as 

 a difficulty that there would result a great number of "specific" names, 

 from which nothing could be seen as to their mutual interrelation. The 

 object with describing especially the many different Ophiopluleus species 

 being mainly to show that also among the Ophiurid larva' there are 

 several well characterized groups, corresponding to what is found among 

 the other Echinoderm larva^ notably among the Echinoid larva?, it was 

 found preferable to give only each type a binominal name, and then to 

 designate the dilTerent species under that type as species a, b, c etc. 

 .\ consequence of this is then further that it is incorrect to designate 

 such new larval type as "nova species"; it is then designated as "nova 



