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 a.s.sociated 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 Coccinellidae_).
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 Scarabaeidae_).
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.
[Ill.u.s.tration: STEVENS PLATE X.
N. M. S. del.
COLEOPTERA]
PLATE XI.
_Euphoria inda._
FIGS. 110-111. First spermatocyte, prophases.
112-113. First spermatocyte, late prophase.
114-116. First spermatocyte, metaphase.
117. First spermatocyte, equatorial plate, _x_ the unequal pair.
118-120. First spermatocyte, anaphase.
121. First spermatocyte, daughter plates.
122. Second spermatocyte, prophase.
123. Second spermatocyte, equatorial plates.
124-125. Second spermatocyte, daughter plates of the two cla.s.ses.
126-127. Second spermatocyte, anaphase.
128-130. Spermatids, _n_ the chromatin nucleolus.