231 



wall between the two cells is more or less oblique, but a hypogynous cell is not cut 

 otf from the lowermost end of the carpogonium as in Choreonema. I have not been 

 able to follow the development of the carpogonia after fertilization, but it must be 

 said that there is nothing to support the supposition of Heydrich that each auxiliary 

 cell becomes a carpospore. The only thing which might favour this view is the 

 fact that the carpospores are produced not only at the periphery but also from the 

 central part of the iloor of the conceptacle, as shown by Heydrich (1. c. fig. 12), 

 and as I have also observed it (fig. 149). But the carpospores do not arise singly; 

 they are produced in short rows, as shown by earlier authors (Solms, Pii.gkr, 

 Minder) for other 

 Corallinaceae. This 

 is shown in fig. 

 149 where a smal- 

 ler (j'ounger) car- 

 pospore is situated 

 under the most 

 developed ones; 

 they have undoub- 

 tedly been produ- 

 ced successively 

 by the sporophyte, 

 but the behaviour 

 of the latter could 

 not be stated. The 

 low cells visible 



under the youngest carpospores are probably parts of the sporophyte (or of the fu- 

 sion cell, if Solms' view is correct); or might there perhaps be more than one 

 sporophyte? The cells situated below the procarps may show lateral fusions (fig. 

 148 D), but it is doubtful whether these fusions have any relations to those of the 

 sporophyte with the auxiliary cells. The evacuated cystocarpic conceptacles remain 

 empty, or become partly filled with regenerating tissue produced from above. 



As mentioned above, this species grows particularly on large boulders; it is 

 therefore probably much commoner than might be supposed from the localities 

 given below, while it does not always become loosened from the stone by the dredge. 

 It occurs in all the three forms quoted by Foslie which however, as stated by this 

 author, are "not well defined, as transitions often appear to occur". It seems to 

 be rather common in the Danish waters to the limits of the Baltic Sea, with the 

 exception of the Limfjord and other fjords where it is wanting. It seems most 

 common in the Kattegat. It occurs in depths of 2 to 19 meters. Tetrasporangia 

 have been met with in April, carpogonia in January and May, and carpospores in May. 



Localities. Sk : ZK'" off Lanstrup, 11,3 m; off Hirshals, 11 — 15 in. — Kii: TX, north of Gnes- 

 liolm (Hirslioliiiencj ; on stones picked up by Hirsliolmene, about 4,5 ni, large crusts; east of Deget ; otf 



Fig. 149. 



IJlliDtluiniiiion pohiinoriiliiiin, vertical sections of cystocarpic conceptacles with carpo- 

 spores. A 200.1. B 3.50:1. 



