ANOMALOUS SERIES. 211 



presence of complicated growth forms in such plants as Fungi, 

 Florideae, Siphoneae, and Lichens suggests what may be termed the 

 architectural view, which Sachs has so greatly strengthened by his 

 recognition of the fact that the apical-cell of Vascular Cryptogams, 

 so far from being " the ruler of the whole growth in the growing- 

 point," represents merely "a break in the constructive system." 

 The more general standpoint has undoubtedly been that of watch- 

 ing the building processes, and this usually finds expression in the 

 discussion of the fate of cell-segments.* 



It is this possibility of drawing a distinction between the con- 

 sideration of a given phyllotaxis system, as the product of one or 

 more genetic spirals, or as a complex of intersecting contact- 

 parastichies, which is so far the most valuable feature of the log. 

 spiral theory ; in that, by regarding the same construction from 

 two different standpoints, prejudice in favour of either one of them 

 may be avoided. 



* Sachs, Physiology, p. 433 : " It was formerly supposed to be possible to 

 characterise the true morphological or phylogenetic nature of an organ by the 

 way in which cell-division took place, and hundreds of treatises and laboriously . 

 drawn plates were devoted to the purpose." 



(I'o he continued.) 



