PLATE 4. — Mazocarpon oedipternum 



Pig. 1. Section of portions of somewhat fragmented sporophylls cut tangen- 

 tial to cone axis and containing megaspores with gametophytes. 



la. Megaspore with gametophyte and archegonium from same section 

 as fig. 1. Compare with plate 3, figs. 5, 6, 7: From C. B. 116 

 A3b (T5). 



2. Megaspore with fusainized gametophytic tissue. Archegonium at 

 apex cut tangentially: From C. B. 116 A3b (T3). 



3. Transverse section of sporophylls (tangential to cone axis) prox- 

 imal to great expansion of dorsal heel, (DH). Sporangium on left 

 appears to have only one lateral sporangial keel (SpK), the other 

 having been eliminated due/ to crowding: From C. B. 136. 



4. Megaspore with partially fusainized gametophyte shrunken away 

 from distal spore wall. A small tangential slice of the archegonial 

 venter is shown: From C. B. 116 A3b (T5). 



5. Archegonium, same as shown near center, fig. 1, at higher mag- 

 nification. Delicate gametophytic tissue and some cells of venter 

 can be seen: From C. B. 116 A3b (T6). 



6. Proximal section of microsporangium adjacent to cone axis. Sec- 

 tion from two planes as in plate 5, figs. 1 and 3; sporangial attach- 

 ment and collapsed T-shaped vestige of subarchesporial pad (s) is 

 shown: From C. B. 124 E (T34). 



7. Median longitudinal section passing through dorsal loop (DL) of 

 sporophyll trace in M. oedipternum f. microphorwm. Scalariform 

 "transfusion" type tracheids occur inside the loop. A shrunken 

 remnant of the ligule (Lig.) is shown above the downturn of the 

 loop: From C. B. 124 E (32). 



8. Distal end of same sporophyll from which fig. 7 was taken, showing 

 relation of sporophyll trace to sporangium, etc. Compare with text 

 fig. 3b. 



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