CHROMOSOME REDUCTION IN THE MICROSPORO- 
CYTES OF LILIUM TIGRINUM.? 
Joun H. SCHAFFNER. 
(WITH PLATES XII AND XIII) 
THE progress recently made in our knowledge of hybrids has given 
a new impetus to the study of chromosome reduction. Unfortunately, 
there is still much disagreement in the accounts of various observers. 
In order to continue my own investigations on a very favorable object, 
the microsporocytes of Lilium tigrinum were selected, since material 
is easily obtained in large quantities. CHAMBERLAIN has studied the 
pollen grain of this plant and has also given figures of the microsporo- 
cyte in the spirem stage. The chromatin granules are exceptionally 
distinct, and this facilitates the correct interpretation of the complex 
figures to be seen in the reduction karyokinesis. 
Recently papers on the reduction division have been published by 
FARMER and Moore, STRASBURGER, MONTGOMERY, WALLACE, and 
others, which are in essential agreement with the interpretations of 
Drxon on Lilium longiflorum and my own observations on Lilium 
Philadelphicum and Erythronium. On the other hand BErcus, 
REGOIRE, and ALLEN have come to somewhat different conclusions. 
The observations of RosENBERG on Drosera have opened up an 
important field of investigation on the individuality of the chromo- 
some. These papers have been reviewed so recently by various 
writers that it is needless to discuss the results here. It is sufficient 
to say that it must appear to an impartial judge that the cytologist is 
at present able to see in his preparations almost anything which may 
be conceived of as taking place in the structures investigated. This, 
however, should not hinder work in such an important field, for the 
proper interpretation can be attained only by continued observation. 
Little can be regarded as certain until there is a more general 
agreement among competent investigators. So far as the present 
research is concerned, the extent and variety of the preparations 
‘Contributions from the Botanical Laboratory of Ohio State University. XXIV. 
183] [Botanical Gazette, vol. 41 
