56 



ticularly tliin, almost as fine as a hair, with the calcareous joints extraordinarily long in pro- 

 portion to the witltli, and the horny joints (3 or 4 in number) only slightly marked, but still 

 when highly magnified easily recognisable, by their greater transparency and faint yellowish ' 

 color. In the latter there could easily be distinguished a more opaque internal part, in the 

 form of a denser cord connecting the 2 opposite projecting joint-surfaces of the calcareous 

 joints with each other, and a more transparent outer part extending some way up along the 

 base of the calcareous joints. In the latter there could in some cases quite clearly be seen 

 an internal canal running through the whole length of the joint. Outside the whole there was 

 remarked an extremely thin exterior skin, the not yet polyp-bearing csenenchym (see fig. 7'). 



The color is in fresh specimens pale orange-yellow, which is especially attributable 

 to the polyps, and partly also to the cfenenchym; but the axis is like the root, externally 

 snow-white, with strongly contrasting dark brown horny joints or knees. 



I have only found this interesting coral in the great depths at Lofoten, namely at 

 the fishing station Skraaven in 300 fathoms, and at the fishing station Risvser down to 400 

 fathoms, the greatest depth there occurring. It lives everywhere only on soft clay or muddy 

 bottom, and seems never like most other corals, to attach itself to the naked rock. 



The species may be characterised in the following manner. 



Mopsea borealis. M. Saxs. 



Polyparium gracile, erectum, indivisum vel parce modo ramosum, ramis indivisis panels 

 et divaricatis, stirpe tenuissimo ubique fere latitudine eadem inque tota longitudine distiucte 

 ai-ticulata, articulis calcareis plerumque valde elongatis, subcylindricis, ad extremitates tamen 

 plus minusve incrassatis, longitudinaliter striatis, nonnullis brevioribus in parte imprimis infe- 

 riore interpositis, nodis cornels (geniculis) brevissimis illis 10'"— 20'" brevioribus ; radice dila- 

 tata, subinfundibuliformi, in ramos plures (3— .5) foliaceos calcareos ssepe irregulariter flexuosos 

 et apicem versus dilatatos et applanatos divisa. Cortex polypifera (speciminum junioruni) in 

 parte modo diniidia superiore distincta, polypis sat magnis spiraliter apicem versus dispositis, 

 tentaculis 8 sat longis pinniferis instructis. Spicula numerosa insequalia et in cute polyporum 

 et in cortice polypifersE acumulata linearia, extremitatibus obtusis, tuberculis numerosis minutis 

 scabra. Color polyporum et corticis polypiferte pallide fulvus; articnla calcarea vero etfoliola 

 radicalia nivea, nodis corneis satm-ate fulvo-badiis. Longitudo speciminis junioris completi 

 90 Mm. latitude stirpis vix 1 Mm.; sed ad magnitudinem longe majorem excrescere potest. 



Habitat ad insulas Lofotenses in profunditate 300—400 orgyarum, fundo argillaceo. 



The present species stands very near to the Mopsea elongata (Isis) Esper' (Mopsea 

 Mediterranea Eisso) also more particularly described by Philippi^ but does not appear to 

 attain so considerable a size as that, which grows more than 2 feet high and 1 foot wide 

 between the longest branches. Moreover our species is far from being so strongly branched 



' Pflanzentliiere Vol. 1. p. 47. Tab. 6. 



* Archiv fiir Natnrsescliiclitc 1842. 1. p. 38. 



