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bably because the division of the cell contents takes place very 

 quickly. One of the youngest stages I have seen is shown in 

 fig. 15 a. We see here that 5 cells are formed, a larger cell below 

 which is always found here at the base of the frond and 4 smaller 

 cells above it. 



Fig. 15 b shows a 

 somewhat more ad- 

 vanced stage of devel- 

 opment , the side- 

 branches of first order 

 here beginning to grow 

 out from the cells in 

 the stalk. This mode 

 of growth is quite in 

 accordance with that 

 in the above-men- 

 tioned species and on 

 the whole the ramifi- 

 cation takes place in 

 the same way as in 

 Struvea elegans, only 

 not quite so regularly. 



As to the cell 

 contents the plate- 

 shaped irregular poly- 

 gonal chromatophores 

 (fig. 15 f) form a net- 

 work in the wall plas- 

 ma. In each chroma- 

 tophore a large pyre- 

 noid is present and 

 under the chromato- 

 phores the numerous 

 nuclei are arranged 

 rather regularly. 



In some speci- 

 mens I have found 

 the cell contents in a great number of the cells in the frond con- 

 gregated in larger and smaller balls, some few in each cell, most 

 probably an aplanospore formation. 



Fig. 15. Struvea anastomosans (Harv.) Piccone. 



a, and b. tops of young- stalks showing development of the 

 frond, c. somewhat more developed frond, d. plant prepared 

 out from a tuft, with rhizoids and ramified stalk so common 

 in this species ; below to the right a young stalk is growing- 

 out, e. parts of the frond showing the mode of attachment by 

 means of tenacula. /. chromatophores with pyrenoids. 

 (a. b. c- d., about 6:1; c, 20 : 1 ; /. 250:1). 



