172 Eigby. — Archesporial and Meiotic Mitoses of Osmiinda. 
Fig. 82. 0 . regalis. Metaphase of the first meiotic division. The quadripolar spindle has 
become bipolar (S.F.). 
Fig. 83. 0 . palustris v ar. aurea. Polar view of an equatorial plate showing twenty bivalent 
chromosomes (H.). 
Fig. 84. As the entire univalent chromosomes proceed to the poles fission widely separates each 
chromosome into daughter chromosomes (H.). 
Fig. 85. Polar view of anaphase ; each univalent chromosome appears double owing to fission 
still widely separating the daughter chromosomes (H.). 
Fig. 86. A second and new fission appears in each daughter univalent chromosome, splitting it 
into two threads and giving it a fenestrated or vacuolated appearance (H.). 
Fig. 87. The nucleus becomes bounded by a limiting membrane ; the splitting apart of the 
sides (threads) of the daughter chromosomes proceeds, and fine transverse strands join the various 
threads to one another (H.). 
Fig. 88. Telophase of the first meiotic division. The identity of the chromosomes is lost to 
view and the sides are resolved into paired beads and parallel threads (S.F.). 
Fig. 89. The onset of the prophase of the second meiotic division. The chromatic nuclear 
contents become concen' rated in rounded masses lying in the portion of the nucleus remote from the 
cell-plate separating the daughter nuclei (S!F.). 
Fig. 90. The nuclear contents mass together (S.F.). 
Fig. 91. Spindle fibres invade the chromatic mass (S.F.). 
Fig. 92. The chromatic segments which are still somewhat indeterminate loosen out along the 
fibres (S.F.). 
Fig* 93 * The chromosome segments become greatly elongated and each appears double, having 
already split into daughter chromosomes (S.F.). 
Fig. 94. Metaphase of the second meiotic division. The daughter chromosomes are completely 
separated before taking up their position on the spindle (H.). 
Fig. 95* As the daughter chromosomes proceed to the poles fission almost completely separates 
them into threads. This is the opening out of the fission prepared for in the alveolization of the 
daughter univalent chromcsomes in the anaphase of the heterotype division (Fig. 86) (H.). 
Fig. 96. Polar view of the anaphase of the second meiotic division. The chromosomes draw 
together and fission closes (H.). 
Fig. 97. The chromosomes separate from one another, and fission once more divides them into 
longitudinal halves or threads which are at first homogeneous (H.). 
Fig. 98. The threads become beaded (H.). 
Fig. 99. A nuclear limiting membrane appears. The beaded threads separate, but the beaded 
skeleton of a few of the chromosomes can still be recognized (H.). 
Fig. 100. The resting stage of the tetrad. The beads become distributed throughout the nucleus 
and thus a fine reticulum is formed (S.F.). 
** ... 
PLATE XII. 
(Photomicrographs by Mr. W. B. Randles.) 
Fig. 1 01. 0 . palustris var. aurea. Spore mother-nuclei in pre-second contraction and in 
diakinesis in the same sporangium, x 400. 
Fig. 102. 0 . palustris var. undulata. Synangium in archesporial division, x 350. 
Fig. 103. Synangium. The spore mother-nuclei of one side are in synapsis and coming out of 
synapsis, the nuclei of the other side are coming out of synapsis, x 200. 
Fig. 104. 0 . palustris \ ar. aurea. Synangium. The spore mother-nuclei of the one side are 
in hollow spireme stage, but as the sporangium lies obliquely the section does not pass through 
them on the other side, x 200. 
Fig. 105. Synangium. The spore mother-nuclei of the one side are in synapsis, and of the 
other side in diakinesis. x 225. 
Fig. 106. Synangium. The spore mother-nuclei of the one side are in synapsis, and of the 
other side in metaphase, x 200. 
