48 AXEL OHLIN, ARCTIC CRUSTACEA. 



This well-kiiown species' is subject to great variations 

 with regard to the form of the rostrum and the number 

 and size of its spines. Bearing this fact in mind, recent 

 authors nsually regard Htjjpoljifc securifrons Norman, which 

 has proved to be identical withHippolijtcLilljeborgiiDANiELSSBJii, 

 as synonymous with Hippolyfe spinns. 



Thus, Spence Bate has deseribed and figured in his 

 Challenger E-eport no less than seven varieties, and one must 

 feel nearly convinced of the identity of both forms. As such 

 these forms are also regarded, among others, by Miers, Hansen 

 and Stebbing, whereas Smith, Särs and Ortmann are of a 

 contrary opinion. 



I ha ve myself examined a good many specimens; but as 

 I could not get Norman' s original description, I do not think 

 it advisable to pronounce with any degree of certainty about 

 it. If that were not the case, then Hippolytc Lilljeborgii must 

 claim priorit}^ as Danielssen published his »Beretning om 

 en zoologisk Reise foretagen i Sommeren 1857» i Nyt Ma- 

 gazin for Naturvidenskaberne, Band 11, which appeared in 

 the year 1861, and Norman's paper was published two years 

 låter. 



DoFLEiN goes so far that he considers Hippolyfe Fhippsi 

 {= H. turgida) as identical with young specimens af H. spi- 

 onts, »besonders solchen, bei welchem das Rostrum noch nicht 

 abgestossen war», 1. c. p. 332. But, as usual, he does not 

 enter upon detailed reasons for this view. He contents 

 himself with the foUowing remark: »Betrachte ich aber das 

 gesammte Material, so känn ich so viel Uebergänge zu H. 

 Phippsi feststeilen, insbesondere zu den als turgida and ma- 

 € ilen fa von Kröyer als besondere Arten beschriebenen Formen 

 von Ph/p2)si, dass ich glaube, es handelt sich nur um eine 

 Art, welche dem Prioritäfsgesefzc gemäss den Namen H. spi- 

 nns Sow. fragen mnss. Diese Annahme wird auch durch die 

 ganz gleichartige Verbreitungsweise der fraglichen Species 

 unterstiitzt (!).^ Die AufFassung von Sp. Bate (Chall. Eep.) 

 leitet zu der hier vorgetragenen iiber.» Strangely enough, he 

 enumerates, however, both Hiptpolyte Phippsi and H. spinns 

 and even H. Lilljehorgi (= H. secnrifrons) as distinct species. 

 It is to be regretted that the author did not give any de- 



^ As he himself points out, this is circnmpolar for both forms. 



