iDEC 1 0 1914 
The Ohio JJ\£aturalist, 
and Journal of Science 
PUBLISHED BY 
The Biological Club of the Ohio State University. 
Volume XV. NOVEMBER, 1914. 
TABLE OF CONTENTS 
No. 1. 
Lie 
NEW 
ROTA 
Humphrey—A Cytological Study of the Stamens of Smilax herbacea.. 357 
Kostir —Additions to the Known Orthopterous Fauna of Ohio. 370 
Jennings— Publications of the Ohio Biological Survey .. 374 
McAvoy —Meeting of the Biological Club. 376 
A CYTOLOGICAL STUDY OF THE STAMENS OF SMILAX 
HERBACEA* 
Lillian E. Humphrey. 
INTRODUCTION. 
There seems to be a general agreement among the various 
investigators of the reduction division, that there is a pairing 
and conjugating, in the first reduction division, of the univalent 
chromosomes to form bivalents, but there is a considerable 
diversity of opinion as to the time of the pairing and fusion. 
Allen, Gregoire, Overton and many others hold the view that there 
is a side to side pairing of the chromatic elements occurring usually 
about the time of “synapsis.” De Vries also claimed that there 
is a side to side pairing, but was not certain when it occurred, 
although it was some time before the separation of the halves 
of the bivalent chromosomes. As a proof of this theory it was 
held that, since a longitudinal split of the spirem is discernible in 
the early stages of the reduction division, the double spirem was 
the result of a conjugation of two simple spirems. But according 
to Schaffner, Fanner and Moore, Mottier and others the early 
split is a longitudinal division of the same nature as that which 
occurs at each vegetative karyoldnesis. The pairing of the 
univalents according to this view must occur very early, before 
the formation of the spirem; and the protochromosomes, which 
in some species are rather definite masses and approximate the 
reduction number of chromosomes, probably represent the end 
of the stage when the pairing occurs. 
* Contribution from the Botanical Laboratory of the Ohio State 
University, No. 85. 
357 
