The Chromosomes of Gryllotalpa Borealis Burm. 
147 
ment and movement of these two chromosomes, may not there also be 
law and order in the arrangement and movement of all the chromosomes 
although the microscope does not reveal the fact to us. That is, may not 
the two components of the bivalent chromosomes which are a result of 
pairing at synapsis be predestined before they enter the spindle to pass 
either to the male or female producing pole and hence take up a definite 
Position on the spindle. These two chromosomes (the large idiochromo- 
some and the odd chromosome) are brought into the male by the egg 
and always pass into the female producing Spermatozoon in maturation, 
This being the case, is it not possible that all the chromosomes which 
are brought into the male by the egg, pass into the female producing 
Spermatozoon and those brought in by the sperm into the male pro- 
ducing Spermatozoon? If such should be the case, the first question 
which naturally arises is in regard to the transmission of characters from 
father to daughter and from mother to son. This difficulty is not an 
insuperable one if chromosomes are complex bodies as present evidence 
indicates they must be if they are the bearers of the hereditary qualities. 
In Order to find a satisfactory explanation for the transmission of charac- 
ters under the above Suggestion we shall have to refer to the synaptic 
Stage. Unfortunately, we are much in the dark as to what actually 
occurs at this time. I believe however, it can be safely stated that the 
majority of evidence is in favor of the view that the maternal and paternal 
chromosomes in some manner or other pair at this time. Whether or 
not the components of each pair separate in one of the maturation divi- 
sions along the old line of union or whether there is a fusion and an inter- 
change of material, we cannot say from the evidence at hand. However, 
certain forms of heredity are more easUy explained if we assume the 
chromosome to be made up of smaller units and that we have an inter- 
change of such units at the time of synapsis. This would give us the 
necessary mechanism for the transmission of any or aU characters and 
according to this scheine we would not necessarily have to assume that 
the sex character and sex limited characters are localizcd in the sex 
chromosomes, if the units which carry such characters are not inter- 
changeable. 
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