from Iceland and Labrador. 109 



20. 7\cbuIij)ora JlaheUarisj Jolinst. 



In tlic form which I refer to this species, the zoarium is flat, 

 depressed, opaque, minutely specked, and sonic wi) at rugose 

 transversely ; the tubes are placed horizontally, somewhat 

 radiately dispixsed, of comj)aratively lar^^e bore, free only for 

 a short distance at the extremity, the free portion not turning 

 upwards, but takin;j^ the horizontal direction. It is more or 

 less regularly tlabellate in its mode of growth. It is well re- 

 presented by Johnston's figure and in Jiusk's ' Cyclostomata,' 

 plate xxiv. fig. 2. It is distinct, in my judgment, from the 

 true T. phalangea. 



Genus DiASTorouA, Johnston. 

 30. Dia^toporaj sp. ? 



A small patch of a Diastopora occurs on a specimen of Cel- 

 hpora incrassata, but in so im])erfect a condition that I cannot 

 determine the species with certainty. I believe it to be refer- 

 able to D. oheh'a, Johnston, which is not imcommon in the 

 Arctic seas. 



Genus Discoporella, Gray. 



31. Discoporella verrucaria^ Fabricius, 



Iceland ; abundant on Sertularella, &c. 



[Bahusia (Lov^n); Spitzbergen (Swed. Exped., teste Smttf)'^ 

 Greenland, Assistance Bay {Sutherland) ; Anticosti and Min- 

 gan Islands; Bay of Fundy (Packard); Orkney and AiTan 

 [Busk).] 



]\Ir. Busk has rightly challenged Smitt's identification of this 

 form with the Discoporella foscul us (mihi). The latter is the 

 Melohesia radiata of Audouin, with whose figure 1 was imac- 

 quainted at the time (1862) of the publication of this species. 



Suborder Ctenostomata. 



Genus Buskia, Alder. 



32. Buskia nttens, Alder. 



Icchind ; very fine, creeping over Ilydroids. 



[Great Britain.] 



This seems to be the only Icelandic form not hitherto re- 

 corded from the Arctic seas. 



Of the 32 species contained in this list, 18 are Britisli ; of the 

 latter, Ilippothoa exjjansa and Idmonea atlantica have only 



