’ 
776 | General Notes. Uy 
also sometimes apparently useless structures, sometimes appar 
ently evidences of degeneration, but throughout are more or less 
distinct marks of harmony with ‘other parts, and of homology 
with other forms. How has this been accomplished? Cleatl 
the crude notion that accidental, purposeless, external fors 
should be sufficient to change by slow degrees one such organist 
into another of a different species is untenable. The doctrine 
action, however, of this internal force is, no doubt, modified 4 
_ accidental secondary causes, which may produce degenerative ® 
well as progressive changes,” 
+} pike P. 298, March 25, 1887. 
sage, for U 
ihe pene, courtesy of Prof, Walter Faxon, of Cambridg® 
oer 
