21 I 



llial. I'vt'ii afler the recent subdivision of Ihe ^real genus Ophiuva (Malsu- 

 Mioto. II. L. (.lark), these two species are left in the same subdivision, 

 the ^enus Oijhiuni s. sir., which would mean that a further subdivision of 

 this f»eiuis is necessary, in lliis connection it is important to notice that 

 most probably Ophiura affinis and the miditerranean (). (irubci, which has 

 unjustly been made a synonym of the fonuer, have larva' of almost iden- 

 tical structure'). I'urther the Ophiopluleus fusiis, described in the present 

 work, recalls the Ophiura (tlbida-hirxa to a considerable degree, so that it 

 might well seem that here again we have the larv;e of two really related 

 forms. ( — O. fusiis being found at the Azores, one might perhaps think 

 of OphiiiKi 'I'lioiilcli Koehler as its parental form — ). Regarding Ophiuni 

 Ir.iliirdlii. tile laiva of which is (juite unique among the Ophiurid-larvae 

 hitherto known through its fenestrated posterolateral rods, it is worth 

 pointing out that this species is very peculiar by its series of pores along 

 the ventral midline of the arms, therein dilTering markedly from the other 

 species of the genus. Upon the whole. 1 would think it very probable that 

 the genus Ophiiiid (or Ophiof/lypfui) in its wider sense is a parallel to the 

 Camarodonta within the Eehinoids, that is to say, representing the most 

 specialized type, in which the "coarser" chaiaclers, if I may use such an 

 expression, have reached such a point of specialization and uniformity that 

 they do not alTord a sufficient base for further classification. The generic 

 characters would then have to be looked for among the minor, mor|)ho- 

 logically less important structures. Just as in liu' CanKuodonta the char- 

 acters of till- i)edicellaria^ and s])icules set in, where the morphologically 

 much more important characters of tin- lest structure are failing as a suf- 

 ficient base for classificalion. This is, of coui'se, only meant as an idea to 

 be tested by further studies. But in any case, it would seem perfectly 

 absurd, in view of the facts here made known regarding the Ophiurid 

 larvae, to diaw the ()|)posite conclusion that, since the larva? of forms so 

 closely alike as Ophiura albida, affmis and lexlurala difTer so markedly 

 from one another, the Ophiurid larvae have no classificatory value at all. 

 While it thus seems an established fact that within the Ophiuroid-larva^ 

 several very distinct generic types may be discerned, it is, at the jjre.sent 

 state of our knowledge, im|)ossible to say whether ■'family"-types also may 

 be distinguished. There is some probability lh;il Ihe family Ophiolhiichidse 

 has a distinct larval type of its own. perhaps also the Ophioeomidaj 

 have a distinct larval type — but very much more knowledge is required, 

 before we can form a safe judgment of this problem. 



') (;oiii|). IIk- iiudioi's |);i|)iT 'Nolrs on llu' di-vfloimiciil and llu' larval tonus ol sonii- 

 Scandinavian l-x-liitiodiTius", p. 135. 



