Natural History of East Finmark. 105 
Horn, vol. vi. Bryozoaires, i. p. 37), and Levinsen has in his 
“Studies on Bryozoa” mentioned a new genus Haplopoma, 
to which he proposes to transfer Microporella impressa, 
Audouin, 
Genus Microporetta, Hincks, 1877. 
Type, Microporella ciliata (Pallas). 
42. Microporella ciliata (Pallas). 
Sverholt (Nordgaard). 
43. Microporella arctica, sp. n. 
1869. Microporella ciliata, Smitt (partim), “Kritisk Forteckning, &c.,” 
Gifvers. Kong], Vet.-Akad. Forhand. p. 6, pl. xxiv. figs. 13-16. 
Zocecia of considerably larger size than is usual in 
M. ciliata. In a young condition the whole front wall is 
brightly glistening and covered with large pores (Smitt, 
fig. 13) ; the crescentic suboral pore is scarcely, if at all, 
larger than the other pores, and often cannot be seen at all. 
The form of the oral opening is as in WV. ciliata, and closest 
examination generally fails to give the slightest evidence of 
oral spines; yet in the case of a few zocecia which were 
situated in a very sheltered position, I have found four or 
five very delicate spines. The ocecium is globose, and in 
this early stage of growth is ornamented with radiating 
riblets; lateral avicularia are very sparingly developed, a 
large portion of the polyzoary often not exhibiting any at 
all. The description just given is that of the young zocecia 
of a thoroughly healthy colony, but in zocecia at a little 
distance from the margin overgrowth rapidly takes place, 
choking up all the pores and even the crescentic pore, and 
smoothing over the ocecium in such a way that the polyzoary 
assumes the aspect of Smitt’s fig. 14. 
Another form is that represented in Smitt’s fig. 16. The 
adult zocecia have the surface granulated more or less 
roughly, the crescentic pore remains open, and the lateral 
avicularium is very rarely developed. 
The first form I have seen only on stones between tide- 
marks at Vadsé, where it is accompanied by Cribrilina 
cryptowcium, Harmeria scutulata, Porella minuta, &c. 
The second form was taken by the ‘ Valorous, 1875, off 
Holsteinborg, Greenland, in 57 fathoms, and was also sent to 
me by Smitt very soon after the publication of his works as 
“ Porina ciliana forma dura, Spitsbergen ”’*. 
* It must be understood that these specimens were received thus 
named before the publication of the last part (pt. v.) of his “Kritisk 
