0. NORDGAARD. [2nd arc. Exp. fram 



sometimes indications of ribs (see fig. 51). The basal wall was not 

 punctured. In the upper half of the lateral wall, there were 2 or 3 

 polyporous rosette-plates. In the mandible of the avicularia 1 > J" 



61. Rhamphostomella spinigera, Lorenz. 



PI. IV, figs. 52-55. 

 Syn. BiDENKAP Kat, p, 32. 



August 4, 1900, Sjopolse Ness, on Balanus; July 8, 1901, Ren Bay. 



There were four spines on the margin of the oral aperture (fig. 52). 

 When there were ooecia, there was genei'ally only one spine on each 

 side. The median denticle is large and characteristic, but variable in 

 form (figs. 53 & 54). In the mandible 1 „ The length is only a 

 little greater than the breadth. The length of the zooecia was from 0.9 

 to 1.2 mm., their breadth about 0.6 mm. 



The frontal wall of the zoo3cia has a reticulated ornament (fig. 55). 

 and is furnished on both sides with a row of marginal pores. In the 

 upper half of the lateral walls there are two or three polyporous rosette- 

 plates. The basal wall is smooth and without puncturing. 



62. Rha,mphostomella, ovata, Smitt. 



PI. IV, fig. 56. 

 Syn BiDENKAP Kat., p. 32. 



September 19, 1900, off Forvisnings Valley, 2-20 fath.; July 12, 

 1901, bay near Land's End; Aug. 16, 1901, Gaase Fjord, about 7 fath. 



The ocEcia are thickly and minutely punctured, not perforated thereby 

 distinguishing this species from the other hitherto known species of this 

 genus. In young zooecia the oral aperture is almost circular, in older 

 ones it is oval. The frontal wall of the zocEcia is punctured and per- 

 forated with large pores; and there may sometimes be traces of ribs. 

 The basal wall has sometimes a peculiar transverse striation. In the 

 mandible I ^g. The length as a rule, is only a little greater than 

 the width, and the free end is rounded. The length of the zooecia was 

 from 0.65—0.78 mm., their breadth about 0.5 mm. 



63. Rhamphostomella, radiatula, Hincks. 



Syn. BiDENKAP Fort., p. 32. 



July 12, 1901, bay near Land's End, on algae. 

 In this species the peristome is elongated upwards over the ooecia. 

 The frontal wall of the zooecia is furnished with ribs and depressions. 



