100 PAT TEIN. 
such a peculiar structure that they give rise to sink holes, and 
the other to sand banks ! 
The facts of variation are of value to the morphologist as 
well as to the biological metaphysician. If, for example, invagi- 
nated appendages are formed, and are formed frequently, it 
shows that in that direction is, in its broadest sense, a path 
of low resistance likely to be followed again and again. The 
same is true of the deviations affecting the margin of the 
mesodermic area, and in fact any of the deviations that occur 
often and in a definite way. 
In the inevitable shifting of internal relations that occur 
in all living organisms, this path is as likely to become a per- 
manent path of least resistance as the other is to remain as 
it is. In other words, the normal and abnormal exchange 
places. 
In conclusion, there seems to me no evidence in the varia- 
tions here described to support the theories which attempt to 
explain heredity by assumptions that leave no room for the idea 
that the ovum is an organism — theories which make the ovum 
a mere receptacle to hold job lots of ancestral organs, to be 
shuffled together and dealt out again during segmentation by 
some archoplasmatic prestidigitator! It makes little difference 
whether the germules, plastidules, biophores, or whatever we 
may choose to call these corpuscular ‘‘ brownies,” come from 
immediate producers of the ovum, or from ancestors ten thou- 
sand generations back; they are things, it seems to me, which 
exist only as mere names that help to bring before the mind a 
few of the factors in an extremely complex process. 
