Plate X.
Odontota dorsalis.
Figs. 69-70. First spermatocyte, metaphase.
71. First spermatocyte, equatorial plate.
72. First spermatocyte, metaphase, showing metakinesis of the heterochromosomes.
73-74. First spermatocyte, anaphase.
75-76. Second spermatocyte, equatorial plates.
77. Second spermatocyte, showing metakinesis of the small chromosome (s).
78. Second spermatocyte, prophase, showing chromosomes longitudinally split.
79-80. Young spermatids, n the chromatin nucleolus.
81-87. A series of stages in the development of the sperm head, showing the various phases in the history of the chromatin nucleolus (n).
88. Cross-sections of nearly mature sperm heads.
89-90. Equatorial plates of spermatogonia of abnormal individual, 15 large chromosomes, 2 small ones.
91. First spermatocyte from same testis, spireme stage, showing 2 small chromosomes associated with 1 large one and a plasmosome.
92. First spermatocyte from the same testis, metaphase showing a similar heterochromosome group.
93. Second spermatocyte from same testis, equatorial plate, showing 2 small chromosomes.
Epilachna borealis (Family Coccinellidæ).
94. Equatorial plate of spermatogonium, 17 large chromosomes and 1 small one.
95. First spermatocyte, spireme stage, showing the unequal pair.
96-97. First spermatocyte, late prophases.
98. First spermatocyte, metaphase, showing chromosomes of different forms.
99-100. First spermatocyte, equatorial plate.
101. Unequal heterochromosome pair from a metaphase.
102. First spermatocyte, anaphase; ordinary chromosomes stippled to show more clearly the metakinesis of the unequal pair.
103. Second spermatocyte, equatorial plates.
104. Second spermatocyte, prophase.
105-106. Abnormal giant spermatids, probably in process of degeneration.
Euphoria inda (Family Scarabæidæ).
107. Equatorial plate of spermatogonium, 20 chromosomes. The 2 smallest are the unequal pair of heterochromosomes (l and s).
108. Resting spermatogonium, showing plasmosome (p).
109. First spermatocyte, spireme stage.
