532 Black — The Morphology of Riccia Frostii , Aust. 
Figs. 69, 70. The sperm cell rounds up somewhat. The blepharoplast is elongating as a narrow 
cord. 
Fig. 71. Sperm cells showing the elongation of the blepharoplast. 
Fig. 72. Vacuole appearing in cytoplasm. 
Fig. 73. Blepharoplast seen as a cord on the periphery of the plasma membrane. 
Fig. 74. View of blepharoplast. 
Fig. 75. View as in Fig. 74 reversed, showing .the two ends of the blepharoplast. 
Fig. 76. Vacuole appearing in the cytoplasm. Blepharoplast somewhat extended. 
Fig. 77. Definite vacuole in the cytoplasm. Blepharoplast consists of a cord on the periphery 
of the cell, extending a little more than half-way round. 
Fig. 78. Showing round form of developing sperm. Blepharoplast as in Fig. 77. 
Fig. 79. Sperm assuming crescent shape. 
Fig. 80. Nucleus becoming homogeneous, and sperm is more crescent-shaped than in Fig. 79. 
Fig. 81. Nucleus homogeneous and crescent- shaped. Blepharoplast extending from it and 
terminating in a head from which two cilia arise. Cytoplasm caught in the curve of the nucleus. 
Figs. 82, 83. Two sperms of the same stage, one with cytoplasm in the curve of the nucleus. 
The head is very definite and the cilia have elongated. 
Fig. 84. Similar to Figs. 82 and 83. Head of sperm very definite. 
Fig. 85. Sperm has elongated somewhat. Very little cytoplasm in the coil of the nucleus. 
Fig. 86. Little later development. Blepharoplast, nucleus, and cilia elongated. 
Fig. 87. About the same as Fig. 86, sperm with cytoplasmic vesicle. 
Figs. 88, 89. Definite head, which stains deeper than any other part of sperm. In Fig. 89 
nucleus and blepharoplast somewhat separated. 
Fig. 90. Mature sperm, showing head, long slender blepharoplast to which nucleus is applied, 
and the two slender cilia. 
