of the aspects of evolution even if their claims to consideration as 
actually demonstrating evolution may be doubted. Evolution 
contravenes heredity. According to the laws of heredity, the 
original sword fern should have produced only sword ferns, but 
the Boston fern appeared as something different. Again, accord- 
PLATE 1 
LEAVES ILLUSTRATING DWARFING. AND SPORTS OF G1ATRAS1 * 
I. Var. ‘ bosloniensis.’ 2. ‘Giatrasi. 3. Dwarf sporl of ‘Giatrasi. 
4. Two-pinnate sport of ‘Giatrasi. 
ing to heredity all Boston ferns should forevermore have pro- 
duced only Boston ferns, but there are at least the six exceptions 
described above. The second point to be noted is the fact that 
evolution is none the less only the rare exception to the law of 
heredity. Probably more than twenty million Boston ferns have 
been grown and sold within the last twenty odd years, but in that 
time only six certain exceptions to heredity have come to life. 
* From Bull. Torrey Club 43- pi 15. 1916 
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