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EXPLANATIONS OF PLATES 



Plate 1 



Dictyophycus r/racilis, new species 



Figure 1. Holotype, X2. Portion of frond with well-preserved regular network 

 of fibers. 



2. Small group of fibers compressed on another indistinct fossil. X2. 



3. Largest specimen observed, probably composed of several thalli. 



X2. 



Plate 2 



DictyophifCiis gracilis, new species 



Figure 1. Portion of network drawn with Lapworth-Parkes microscope to show 

 irregular character of meshes. X4. 



2. Portion of network with fine pores; also traces of parallel lines. 



X4. 



3. Specimen retaining softer part of the thallus besides the network of 



ribs. X4. 



