156 THE ANATOMY AND AFFINITY OF STROMATOPTERIS MONILIFORMIS, METT. 
Figs. 9 and 10. Steps in formation of typical “ open ” foliar trace within the. base of the above-mentioned 
petiole. x 30. 
Figs. 11-13. Steps of first branching in base of distal swelling in left-hand branch, and leading to the 
liberation of the foliar trace of the right petiole. x 30. 
Figs. 14-16. Steps of second branching within the above-mentioned swelling, resulting in the forma- 
tion of the stele which enters the short columnar branch and the trace for the middle petioles, x 30. 
Fig. 17. Section of leaf -trace of middle petiole when the latter is free from the axis, x 30. 
Figs. 18 and 19. Successive sections in the columnar arrested axis standing between the left-hand and 
middle petioles. x 30. 
Fig. 20. Incomplete specimen of Stromatopteris from which the above-mentioned sections are taken. 
x § . 
Plate II. 
The sections depicted in this plate all belong to specimen depicted in fig. 41. 
Figs. 21-23. Steps of stelar division preparatory to basal branching, x 30. 
Figs. 24-27. Steps of division leading to total abortion of a left-hand branch. x 30. 
Figs. 28-31. Steps of second branching. x 30. 
Figs. 32-35. Steps of third branching. x 30. 
Figs. 36-40. Steps of stelar division within the nodular swelling of right member of this latter 
branching, and showing the reduction of the axial stele. x 30. 
Fig. 41. Incomplete specimen of Stromatopteris from which the above-mentioned sections are taken. 
Plate III. 
Figs. 42—52. Steps in formation of typical foliar trace in right-hand aborted leaf of the specimen figured 
on Plate II, and the stelar reductions which characterise the terminal portion of this leaf. x 30. 
Figs. 53-56. Steps in the single branching of the left limb of the above-mentioned specimen. x 30. 
Fig. 57. Section of the foliar trace which enters the left petiole of the above-mentioned specimen. x 30. 
Fig. 58. Photographic reproductions of the fertile leaf and the first specimen of Stromatopteris on which 
this paper is founded. x \. 
Fig. 59. Photographic reproductions of specimens of Stromatopteris figured by Christ, and showing 
branching of a single leaf, x J. 
Figs. 60 and 61. Sections of a basal and a terminal portion of the rachis of Stromatopteris showing the 
stele with extra-marginal pinna-trace supply, x 30. , 
Plate IV. 
Figs. 62 and 63. Back and front views of the same. Sporangium of Stromatopteris , with massive trans- 
verse annulus and vertical dehiscence, x 60. 
Figs. 64 and 65. Back and front views of a small sporangium with oblique uniseriate annulus, x 60. 
Fig. 66. Section of sorus bearing leaf of Stromatopteris. x 45. 
Figs. 67 and 68. Back and front views of a large sporangium with uniseriate oblique annulus. x 60. 
Figs. 68 and 69. Two views of the thin- walled spores of Stromatopteris x 280. 
Figs. 71 and 74. Back and front views of a large anomalous sporangium of Stromatopteris. x 60. 
Figs. 72 and 73. Top and bottom views of a small anomalous sporangium of Stromatopteris. x 60 
