MULTIJUGATE TYPES. 195 



The method of regarding such systems as controlled by two or 

 more genetic spirals neither presents any further explanation of 

 the phenomena, nor is more generally useful in practice, than it 

 would be if every parastichy line were called a genetic spiral, since 

 all equally go on winding indefinitely. It is interesting to com- 

 pare such a standpoint with the original conception of " Multiple 

 Spirals" put forward by Bonnet and Calandrini. 



