ON THE LYSIANASSA MAGELLANICA ETC. 



7 



that genus is according to Woodward represented in the Antarctic Ocean 

 by some few species, but according to H. & A. Adams 1 ) by only one, the 

 Clio anstralis BRUG. The genus of Buccinnm, including about 20 typical 

 species, also belongs only to the arctic and antarctic seas. The same is 

 the case with the genus Tr&phon , containing about 14 species, the chief 

 part of which are from the Northern Seas (Woodward). 



The Bryozoa often present examples of more widely spread geo- 

 graphical distribution than other animals of the lower section, and of these 

 the same species have been occasionally met with in both the arctic and 

 antarctic seas. Thus for example the Retepora cellulosa, which is not un- 

 common in our arctic region, has by Ross been found at a depth of 1G20 

 feet in the South Polar-Sea 2 ), Lepralia Malusi Busk, at Cape Horn, in 

 the Mediterranean and in northern Europe, and Flustra foliacea Esper in 

 the Southern Ocean and in Northern Europe 3 ). 



The difference between the Crustacea, which strictly belong to the 

 Arctic & Antarctic Zones, is not so great as that between them and those 

 which are found in the warmer seas, but we know as yet of only 2 species 

 common to both, both of the lowest group, and only a few peculiars genera 

 common to both Zones. Our knowledge af the Crustacea of the Antarctic Re- 

 gions is however as yet so imperfect as not at present to justify the utte- 

 ring of a decided opinion on the relation, that may exist between the ant- 

 arctic & the arctic Zones in this matter. The following genera are common 

 to both zones. Order Podophthahnia: Lithodes Latr., Munida Leach, 

 Euphausia DANA 4 ). Suborder Amp hip o da: Orchestia LEACH, Anonyx 

 KROYER, Iphimedia H. RATHKE, Atylus LEACH, Amphithoe LEACH, Hyperia 

 Latreille, Themisto Guerin-Meneville , Cyamus Lamarck. Suborder Is o- 

 poda: Idothea FABRIC, Glyptonolus EIGHTS, Porcellio LATR., Oniscns LlN., 

 Jaera LEACH, Sphaeroma Latr. 5 ); Order Copepoda: Cetochilus ROUS- 



') The genera of recent Mollusca. T. 1. pag. 62. 



2 ) Bronn : Klassen und Ordnungen etc. 3 Bd. p. 90. 



3 ) Ibid. p. 92. 



4 ) Mr Th. Fries has kindly presented to our University's Zoological Museum 

 some specimens of a Schizopod that appears to constitute a link uniting the Euphausia 

 Dana with the Thysanopoda M. Edwards, found by him after a storm thrown upon 

 the shore of Warangerfjord in the norwegian Finnmarken. The last pair but one of 

 the truncal feet has only the outer branch or palp, very small, and an almost im- 

 perceptible rudiment of the inner branch or stem. We shall call it Euphausia gladalis 

 n. sp. , as it appears to approach somewhat nearer to the genus Euphausia. 



5 ) We have found at Oresund (the harbour of Landskrona) a species of the 



