306 



Cardiff: Synapsis and reduction 



BOTRYCH1UM OBLIQUUM 



Figure 6i. Very early archesporial cell ; chromatic material in the form of small 



granules and slender discontinuous threads. 



FIGURE 62. Early mother-cell ; chromatin beginning to form continuous threads; 



pairing of threads apparent in places. 



Figure 63. Portion of chromatin from presynaptic 

 nucleus ; chromomeres still quite distinct ; pairing 



evident. 



Figure 64. Section of nucleus previous to synapsis ; 



chromomeres losing their identity. 



Figure 65. Portion of nucleus a little later than 



figure 64. 



Figure 66. Threads from knot just previous to 



synapsis. 



Figure 67. Entire nucleus just previous to synapsis, 



moieties in most cases having united. 



Figure 68. Mother-cell in synapsis. 



Figure 69. Threads disentangling from knot ; bivalent character shown in places ; 



threads homogeneous throughout. 



Figure 70. Loose postsynaptic spireme ; beginning of transverse division. 

 Figure 71. Formation, by transverse division, of heterotypic chromosomes; many 



chromosomes showing bivalent character. 



Figures 72 and 73. Prophase of first division; thick heterotypic chromosomes; 



several show undoubted bivalent character. 



Figure 63 



