12 0. NORDGAARD. [2nd arc. exp. fram 



area were exactly the same, and it also had no lateral avicularia, 

 but, on the other hand, one of medium size above the ooecium. On the 

 distal part of the oral margin there were a couple af spines, one of 

 which formed a cylindrical tube, while the other was pointed. This 

 form will therefore have to been referred to var. armifera, of which 

 typical specimens were found in the same place (August 30, 1901), with 

 the length of the area from 0.52 to 0.65 mm., and its breadth 

 0.39 mm. A colony was found on Smittina jeffreysi from Gaase Fjord 

 (August 16, 1901), which best answers to Hincks description of M. 

 armifera^. 



The zocecia were very large, their length being from 1.0 to 1.3 mm., 

 their breadth 0.6 mm. The area occupies almost the whole of the 

 front of the zooecium, its length being 0.78 mm., its breadth 0.5 mm. 

 Occasionally a spine was found on one side, and a small avicularium 

 on the other. The lateral walls of the zocEcia were furnished with 4 

 polyporous rosette-plates, and the transverse wall between the 

 zocecia had a belt of pores on its lower part. The pores were thus not 

 gathered into the two groups of rosette-plates, as is the case, for instance, 

 in M. nigrans (fig. 7). 



The ooecia were small and spherical, with a transverse rib that was 

 not so marked as usual. With the ooecium there generally appeared an 

 unusually large avicularium with pointed mandible, which would some- 

 times be hooked, sometimes straight. In addition to this, there was also 

 sometimes seen a small, medially-situated avicularium at the proximal 

 end of the zooecium, with a pointed mandible, that was directed 

 sidewards. Occasionally, moreover, a small lateral avicularium was ob- 

 served, of which the pointed mandible was directed either downwards or 

 to the side. 



Among the specimens from the 2nd Fram expedition, I found no 

 Membranipora that I could put with the boreal M. unciornis, Flem. 



14. Membranipora nigrans, Hincks. 

 PI. I, figs. 7-9. 



1882. Membranipora nigrans, Hincks, Report on the Polyzoa of the Queen Char- 

 lotte Islands. Ann. Mag. Nat. Hist., ser. 5, vol. 10, p. 9 

 (reprint), PI. 19, fig. 2. 



1900. Membranipora macilenta, Waters, Journ. Linn. Soc, vol. 28, p. 61, PI. 8, fig. 10. 



1903. Callopora nigrans, Norman, Ann. Mag. Nat. Hist., ser. 7, vol. 11, p 593, 

 vol. 12, PI. 8, figs. 1 & 2. 



Ann. Mag. Nat. Hist., Ser. 7, vol. 9, p. 155, PI. 8, fig. 4. 



