2 ARKIV FÖR ZOOLOGI. BAND 9. N:0 6. 



The internal antennse are short with two filaments of which 

 one is considerable longer tban the other one. All articula- 

 tions of the peduncels of these carry small spinse. The lateral 

 tooth of the internal antennse is large. The filaments of the 

 external antennae are divided into a large numher of joints. 

 The mandibel are provided with a two-jointed palpus. 



The two anterior periopods (chelipeds) are typically 

 cheletse. The first pair is shorter and more thick-set than the 

 second pair, which has a narrow carpus, divided into seven 

 articulations. The periopods are all without exopodits. The 

 pleurobranchies are found but the arthobranchies are missing. 



The third abdominal segment has a bent spina directed 

 backwards. In order to protect the roe the anterior epimera 

 are very large especially the second one, which is shaped 

 like a saddle. The 4th and 6th epimera carry a spina on 

 each side at their lower edge. The 6th segment has one pair 

 of teeth in its upper anterior margin. The telson is broad 

 and very powerful. 



All the specimens are females and carry roe; of the 

 five specimens in the collection the largest one has the foUo- 

 wing dimensions. 



Total length of the specimen 88 mm. 



Length from the posterior margin of the carapace 



to the apex of the rostrum 33 mm. 



Length of the rostrum 16 mm. 



» of the carapace 17 mm. 



These specimens were found at Vaigattet, Greenland: 

 depth 315 m.; bottom: clay with stones. Sofia exp. ^^/s 

 1883. 



This species is easily recognised owing to its long and 

 strong rostrum with the sharp teeth and is no doubt a new 

 species of Spirontocaris. It is a remarkable fact, that this 

 species has not hitherto been described as it belongs to a 

 region, where the fauna of Decapods is very well known. 



It is not uncommon within the genus Spirontocaris, that 

 the males differ from the females in several of their morpho- 

 logical characteristics. The males of the Spirontocaris po- 

 laris (Sabine) have often no teeth on the upper edge 

 of the rostrum {= Hippolyte horealis Kröyer), the males of 



