418 BOTANICAL GAZETTE [November 



Figs. 34-38. — Stages in the development of the embryo; X645. 



Fig. 39. — Older stage of embryo; X450. 



Fig. 40. — Another view of the basal part of the embryo shown in fig. 39; 



X45°. 



Fig. 41.— Tip of mature sporophyte; X180. 



Fig. 42. — Foot of mature sporophyte; X180. 



Fig. 43. — Part of young embryo showing sporogenous tissue and walls, 

 and length of sporogenous tissue; X860. 



Fig. 44. — Part of sporogenous tissue showing the beginning of contraction 

 of protoplasts; X860. 



Figs. 45-47. — Stages in development of sporogenous tissue; X860. 



Fig. 48. — Early stage of lobing of mother cell; X1600. 



Fig. 49. — Late stage of lobing of mother cell; X 1600. 



Fig. 50. — Mature spore mother cell; X1600. 



Fig. 51. — Mature spore mother cell just before reduction division; X 1600. 



Fig. 52. — Spore mother cell during reduction division; X1600. 



Fig. 53. — Homotypic division of spore mother cell; X1600. 



Fig. 54. — Young spores nearly separated; X1600. 



Fig. 55. — Surface view of echinations of spore coat; X1600. 



Fig. 56. — Mature spore; X1600. 



Fig. 57. — Mature spore with two nuclei; X1600. 



Fig. 58. — Mature elater; X1600. 



Pellia epiphylla 

 Fig. 59. — Outline of spore mother cell from living material; X 1300. 



Aneura pinguis 



60-64 



300 



600 



-67. — Outlines of sporogenous cells from preserved material; 



Pallavicinia Lyellii 



Figs. 68-75. 



1300 



600 



76-83. — Outlines of sporogenous cells from preserved material; 



Cephalozia bicuspidata 



Figs. 84-87. 



1300 



, — Outlines 



600 



Porella platyphylla 



X1600. 



94-99. — Outlines of spore mother cells from living material; X 13°°- 

 100-102. — Outlines of spore mother cells from preserved material; 



