AMT C24/8

The relatively unchangeable anatomical pattern, or else secretions from the new structures ensure that the wavelength of the chemical pattern increases with that of the anatomical pattern.

A special point arises in connection with the daisy, the formation of the ring of thirteen bracts. This number is very constant. The author does not recall finding any specimen with a different number of bracts, excepting a very few deformed or damaged specimens. It is suggested that this ring of bracts is formed as follows. Within the band of lattice pattern there appears at some stage a ring of reduced activity, so that the band becomes divided into two separate bands. The more distal of these bands continues its development and eventually forms the floret pattern. The proximal band is however rather narrow and weak however (it is pointless to enquire way). This narrowness results in its degenerating from a lattice pattern into a ring pattern, i.e. into a ring of maxima uniformly placed around the cylinder. This process id described in ?. The number if maxima in the ring under these circumstances will be one of the three principal parastichy numbers of the lattice, usually the largest of the three. In view of the fact that the daisy develops according to the normal Fibonacci pattern this number must be expected to be a Fibonacci number, as it is.