TH E 
HEW PHYTOLOGIST. 
Vol. i., No. 3. March 19TH, 1902. 
/ 
DESCRIPTIVE MORPHOLOGY.—PHYLLOTAXIS. 
By A. H. Church. 
O N attempting to construct a morphologically accurate descrip¬ 
tive account of any given flowering plant, which shall 
he something more than the curiously inept description still 
often given by systematists as a sufficient guarantee of specific 
rank, one is abruptly hi ought face to face with a whole series of 
problems due to the inadequacy of the terminology which has been 
handed down for generations as the traditional language of the 
science; and nowhere is this more obvious than when dealing with 
floral structures ; so many expressions which are in almost daily 
botanical use being purely conventional and admitting of no 
scientific definition whatever. Whether one considers terms based 
on erroneous conceptions of the structure of the adult flower by 
botanists who were entirely ignorant of developmental processes, 
drawn from the writings of Linnaeus, De Candolle and Jussieu; 
or even the floral diagrams of Wydler and Eichler, one is constantly 
tempted to absorb purely conventional standpoints as actual facts: 
for example, what strictly scientific conception even now defines the 
limits of perigyny and cpigyny ; or again, where is there any strict 
evidence whatever that “Sepal No. 2” of the characteristic 
quincuncial calyx of pentamerous flowers really is mathematically 
median posterior ? 
It is this difficulty of constructing for oneself, to say nothing 
of obtaining elsewhere, a good intelligent and intelligible description 
or diagram of even the commonest flower—one need go no further 
than the Buttercup for a type- that lies at the root of the present 
unsatisfactory nature of Elementary Botany. It is cleai that the 
subject must be approached with an entirely unprejudiced, and 
preferably unorthodox mind; and in so dealing with the construction 
of a plant shoot as a stem bearing leaves, that is to say, an axis 
and its appendages, the first step toward the attainment of such 
