PLATE 5. — Mazocarpon oedipternum 



Fig. 1. Forma microphorum; slightly oblique longitudinal (near -radial) 

 and transverse sections at the tip of a cone, obtained simultaneously 

 on a single peel. Ruled white line indicates juncture of the two 

 planes of section: From C. B. 124 E (T38). 



2. Forma megalophoy^um; transverse section for comparison with sim- 

 ilar sections of f. microphorum in figs. 1 and 3: From C. B, 136. 



3. Forma microphorwm; section taken in the same manner as that 

 shown in fig. 1 but through the basal part of a different cone. 

 Longitudinal section is tangential. Sterile sporophylls are shown 

 at the cone base. Stele has disintegrated and is absent in the 

 oblique transverse part of the section: From C. B. 124 E (T38). 



4a. Microspores showing papillate surpace of exospore. 



4b. Exospore more or less torn off, exposing the endospore which is 

 shown carrying the trilete sutures. A thickened darker spot is 

 shown at the tip of each pyramic segment of the endospore. Spore 

 photos by E. A. Piatt. 



5. Section at higher magnification taken slightly tangential to micro- 

 sporangiate cone apex. Vascular traces (v) extend into undevel- 

 oped sporophylls at cone tip. Strict verticillate arrangement is 

 evident: From C. B. 124 E (T32). 



6. Forma megalophorum; tangential section of cone shown in fig. 2 

 adjacent to the plane shown on a slant at the left of that figure. 

 Sporophylls are apparently in verticills: From C. B. 136. 



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