ON THE DEVELOPMENT OF TUBULIPORA. 101 



presenting specimens from Spitzbergen, the peculiar form of 

 the flattened ooeciostomes^ with their radially arranged flat 

 sides, is indicated, while the flattened form is expressly men- 

 tioned on p. 457. I have not seen specimens so finely de- 

 veloped as that shown by Smitt in his fig. 6, in which the 

 radial serial arrangement of the zooecia is strongly marked (as 

 many as twenty being stated to occur in one series). The 

 diff'erence between Smitt's specimens and those examined by 

 me may, however, be seasonal, as suggested under the last 

 species. 



It may be remarked that Smitt's conclusion that T. pha- 

 langea is a synonym, partly of T. lobulata, Hass., and partly 

 of T. flabellaris, Fabr., does not appear to have been based 

 on an examination of actual specimens of the first-named 

 species. 



Tubulipora aperta, n.sp. (figs. 2, 3). 



Tubulipora fimbria, Smitt (40, pp. 401, 452, pi. ix, fig. 5). 



P Tubulipora fimbria, Levinsen (26, p. 75, pi. vi, figs. 45 — 50). 



Zoarium entirely adnate, pyriform, flabelliform, or lobed. Zooecia not 

 serially connate, or only exceptionally united in very short series. Ectocyst 

 with few pores. Ooeciostome about 280 fi in diameter, larger than an orifice, 

 more or less funnel-shaped ; the ooeciopore opens upwards, and is circular or 

 oval. Tube of the ooeciostome usually more or less free, and diverging from 

 the zooecium on which its base is recumbent, the edge of the ooeciopore often 

 resting on the wall of another zooecium. Accessory openings sometimes 

 present at the ends of the lobes of the ovicell. 



Common on the fronds of Laminaria saccharina in Norway. My 

 largest colony is 5'25 mm. in transverse diameter. 



This species, which I believe to have hitherto received no 

 distinctive specific name, has been described and figured by 

 Smitt under the name of T. fimbria. This name, applied by 

 Hincks to T. plumosa, Thomps., was given by Lamarck to 

 an immature specimen of Tubulipora, of which the locality 

 is not recorded, and I give my reasons for not accepting it 

 on page 107. The name aperta is suggested in reference to 

 the wide ooeciopore, which is usually ' clearly visible from above. 



