230 POKINID.E. 



Bahusia^ at great depths, rare (Loven) : between Norway 

 and Spitzbergen, 111'' 5' N. lat., 10° 5' E. long., in 600 

 fathoms, muddy ground (Dr. Chydenius, Swed. Exped.) : 

 Bohuslan, 120-130 fathoms (Olsson) : Florida, 82-450 

 fathoms, abundant ; off Portugal ; Azores (Smitt) . 



This species varies in the habit o£ growth, the branches 

 being in some cases (as Sars has remarked) erect and com- 

 pact, whilst in others they spread out horizontally and on 

 all sides. The cells are ranged in four longitudinal rows, 

 alternating regularly with each other, so that the opposite 

 cells are on the same level. The avicularia are somewhat 

 irregular both in number and position ; besides those 

 which have been mentioned, there is occasionally one of 

 larger size and much raised on the front wall. Except in 

 the younger portions of the colony, the zocEcia are not 

 usually well defined ; as calcification proceeds, their 

 boundaries are almost obliterated, and the zoarium pre- 

 sents a uniform surface, traversed continuously by the 

 undulating furrows, which wind round and inclose the 

 pores and avicularia. 



b. Zoarium incrusting. 

 PoRiNA TUBULosA, Norman. 



Plate XXXII. figs. 6-9. 



Lepralia TUBULOSA, Normaii, Shetland Pol., Rep. B. A. 1868, 308: Hincks, 



on Arctic Polyzoa, Ann. N. H. January 1877, 101, pi. xi. 



fig. 8 (see also Ann. N. H. July 1877). 

 Anarthropora monodon, forma minuscula, S/nift, (Efv. af Kongl. Vet.- 



Akacl. Forh. 1867, Bihang, Krit. Forteckn. iv. 7 & 65, pi. 



xxiv. figs. 20-22. 

 CvLiNDROPORELLA TUBULOSA, Hincks, Ann. N. H. Dec. 1877, 528. 



Zocecia separated by very shallow sutures and disposed 

 in regular linear series, ovate and somewhat depressed 



