g2 BOTANICAL GAZETTE [AUGUST 
tion in Gladiolus, Iris, Disporum, and Hesperaloe. As these 
types are representative of related families, it is not surprising 
to find such a resemblance. This method of spindle develop- 
ment, however, is not peculiar to these families, as the follow- 
ing descriptions of the conditions existing in Hedera will show. 
The young anthers containing the pollen mother-cells of 
Hedera helix are extremely small and difficult to handle. But 
after being fixed in the field and imbedded, the difficulties are 
mostly overcome, for the mother-cells stain very easily with the 
triple stain, and the various stages in the development of the 
spindle of the first and second division are readily obtained. 
The mother-cells in Hedera are much smaller than the lilia- 
ceous plants, but the nuclei are relatively much larger. As 
division approaches, the amount of nuclear sap is very great, and 
as a result the nucleus occupies one-half the space of the cell. 
Before any kinoplasmic differentiation takes place, the cyto- 
plasm presents a uniform granular reticulum, but this appears to 
be slightly denser in the vicinity of the nuclear membrane, sug- 
gesting the condition that exists in Cobaea and Gladiolus. As 
soon as the chromatin has segmented to form the chromosomes, 
the cytoplasm in contact with the nuclear membrane becomes 
differentiated into a thin weft of fibrils, which stain an intense 
blue. The development of the weft is essentially the same as 
that described for Gladiolus, Iris, Disporum, and Hesperaloe. It 
consists at first of only a few threads, which’ interlace with each 
other and run more or less parallel to the nuclear membrane. 
The fibrils nearer the membrane stain a very deep blue, but those 
farther out stain less, and as they merge into the surrounding 
orange-staining cytoplasm, they are slightly granular and are no 
longer to be distinguished from the reticulum of the latter (/g- 
24). The origin of the fibrils of the weft is apparently due to 
the change in the structure of the threads of cytoplasm, 4s 
described in Iris, Disporum, and Hesperaloe. As in these plants, 
the weft is uniformly thick in the early stages of its formation, 
but it soon develops projections at irregular intervals, producing 
the primary cones of the multipolar figure (figs. 25; 26). 
As the primary cones grow outward, the fibrils composing 
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