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and larger, first making the thallus sack-shaped (fig. 4) and at last 

 it will be torn and disc-shaped. These old disc-shaped specimens 

 can be very large; I have collected specimens with a diameter of 

 about 12 cm. 



As to the hapteræ found along the edges of the cells, these 

 all grow out from quite small cells which are very similar to the 

 small lentiform cells found in Valonia 1 ). These small cells are 

 arranged in series (most often 3) along the edges of the large ones 

 (fig. 6 d) and very regularly, alternately opposite each other in such 

 a way that the hapteræ growing out from the small cells attach 

 themselves to the wall of the neighbour cell just in the intervals 

 between the small cells on it (fig. 6 e, f). In this way the large 

 cells are very firmly fixed together. The small cells are, when 

 seen from above, oval oblong sometimes also quite circular. One 

 to two hapteræ grow out from them (fig. d, e). 



The small cells also occur abundantly upon the sack-like out- 

 growth from cells at the base of the plant (fig. 4, 5 c, d, e). Where 

 their walls come near to the substratum the small cells are present 

 in great number and from them rhizoids grow out and attach the 

 plant. Here the arrangement of the small cells is more irregular. 



With regard to the wall-plasma, we find, as also pointed out 

 by Askenasy and Miss Crosby, the numerous rather large 

 roundish-polygonal chromatophores of the wall plasma becoming 

 connected with thin prolongations forming in this way a more or 

 less open net-work (fig. bf). In the chromatophore one— three 

 large pyrenoids are present. Near to the one side of the chroma- 

 tophores the numerous oblong, rather large nuclei are met with. 



In the small cells also some few chromatophores with pyre- 

 noids occur (fig. 6 e) , furthermore also a single nucleus or in the 

 larger oblong cells even two. That chromatophores occur in the 

 small cells is also mentioned by Heydrich I.e. p. 468. The outer 

 wall shows cross-wise striations. 



As already mentioned above, I consider Harvey's description 

 of Dictyosphœria favulosa to be in several respects very good, this 

 especially applying to his description of the appearance and habit 

 of the plant. As to the cell division, "the repeated quadrisection 



*) It has been of interest to me to see what Heydrich writes about this 

 matter; p. 468 (I.e.) he says: "Jede Fibula bildet an der Stelle, wo sie der 

 Wand der sie erzeugenden Zelle ansitz, eine uhrglasförmige Vertiefung". 



