June, 1909.] Reduction Division in Hyacinthus. 
539 
THE REDUCTION DIVISION IN THE ANTHERS OF 
HYACINTHUS ORIENTALIS.* 
Edith Hyde. 
There are many problems in connection with the reduction 
division, which have not been satisfactorily solved. It was, 
therefore, determined to take up the problem on some plant 
which would show the nuclear structures as distinctly as possible. 
The plant finally selected for the investigation was the common 
hyacinth, Hyacinthus orientalis L. 
The dry bulbs of the common hyacinth were planted in the 
greenhouse at various intervals during the Fall of 1907. A 
bulb was opened and examined almost every day, but it was not 
until the first week in November that the desired stages were 
secured, since it was some time before it was ascertained how 
long the dry bulbs must remain in the ground before reduction 
begins. This depends entirely on the time of planting. If the 
bulbs are put in the ground early in the fall it will be some time 
before reduction takes place. The desired stages were finally 
secured in bulbs which were planted in the last week of October, 
and which remained in the ground less than a week, showing 
that slow development takes place in the bulb while in the dry 
state. All of the material killed on the days from the 1st to the 
4th of November showed the various reduction stages, and even 
in the individual bulb nuclei ranging from early microsporocvtes 
to tetrads were found. The usual methods of killing and 
imbedding were used and the sections were cut from 10-12 mic. 
thick. The slides were stained most satisfactorily with Delafield’s 
Haemotoxylin. This study was begun under the direction of 
Prof. R. F. Griggs and was completed under Prof. J. H. Schaffner, 
to both of whom the writer is greatly indebted for kindly assist¬ 
ance and suggestions. 
In the younger anthers many nuclei were found showing the 
last division previous to the formation of the microsporocvtes 
(figs. 1,2). In these nuclei the spirems showed a linin thread 
with definite granules. There is evidently no long resting stage 
in the sporocvte previous to reduction and this makes it difficult 
to recognize the young sporocytes from their mother cells, the 
two being present in the sporangium at the same time. A 
tendency toward indefinite massing of the chromatin (figs. 3, 4) 
in the early sporocytes, gradually disappears as the threads of 
the network become more prominent (fig 5). There does not, 
however, seem to be any definite massing of the chromatin into 
* Contributions from the Botanical Laboratory of Ohio State Uni¬ 
versity, XLVII. 
