656 THE ANATOMY AND AFFINITY OF PLATYZOMA MICROPHYLLUM. 



Fig. 52. A section of the stele of Platyzoma, showing the origin of a root-trace from the outer xylem- 

 cylinder. ( x 15.) 



Ki,^ r . 53. Transverse section of a root-trace on its way out through the cortex of the rhizome. ( x 15.) 

 Fig. 54. Transverse section of a root of Platyzoma. ( x 15.) 



Plate IV. 



Figs. 55-58. A small sporangium of Platyzoma seen from behind, in front, above, and below. The 

 irregularities in the nearly vertical annulus, and the interruption of the annulus by the stalk, are 

 shown. ( < 36.) 



Fig. 59. A sporangium with almost globular capsule, and an oblique — though almost regular — 

 annulus. ( x 36.) 



Fig. 60. The wall of a sporangium opened out so as to show the irregular and broken annulus. ( x 36.) 



Figs. 61, 62. Two views of a rarer type of small sporangium of Platyzoma. The annulus is almost 

 horizontal, but is irregular and broken, and no clearly denned stomium is developed. ( x 36.) 



Fig. 63. Transverse section of the stele of Platyzoma, at a point where the xylem towards the lower 

 surface is broad. The groups of tracheides appear lohite in the photograph, and the chains and groups of 

 xylem parenchyma are black. ( x 36.) 



Fig. 64. A spore of the intermediate size. ( x 90.) 



Fig. 65. A spore of the smallest size. ( x 90.) 



Fig. 66. A spore of the largest size. ( x 90.) 



Figs. 67, 68. A front and a back view of one of the largest sporangia of Platyzoma. ( x 36.) 



