Davis.— Spermatogenesis. 
Fia. 69. 
Fre. 70. 
PLATE 5. 
Figs. 69-73. Stetroxys trilineata. 
Stage e, primary spermatocyte. The monosome is seen above and 
at the left. 
Stage g, primary spermatocyte. The monosome is seen at the 
lower side of the nucleus. 
Figs. 71, 72. Stage h, primary spermatocyte. The monosome is distin- 
Fie. 73. 
Fig. 74. 
Fie. 75. 
Fig: 76. 
Fie: 77. 
guished from the autosomes by its more compact structure. 
Metaphase of first maturation division. The monosome is con- 
nected with only one pole. , 
Metaphase, first division of Melanoplus femoratus. The mono- 
some is seen at the right connected with only one pole. 
Figs. 75-81. Dissosteira carolina. 
Semiresting stage of second spermatocyte. The monosome is seen: 
below in the figure and at a lower focus. 
Prophase of second division. 
Metaphase of second division. 
Fias. 78-79. Anaphase of second division. The figures are from two 
Fig. 80. 
Fig. 81. 
Fig. 82. 
successive sections of the same cell. All the chromosomes Jare 
shown. 
Telophase of second division. 
Spermatids. The monosomes still retain their compact structure. 
Spermatid of Stenobothrus curtipennis. The monosome is still 
compact. 
