70 WorsdelL — The Structure of the 
seminiferous scale he regards the development as an unreliable 
factor ; that this is so is shown by the circumstance that 
Strasburger and Eichler both rest their very different views 
on developmental evidence. The development of the semini¬ 
ferous scale, he says, is a ‘ heterodox ’ one. Nature here 
takes a short cut; instead of forming a bud with two distinct 
lateral leaves (Fig. 3), the seminiferous scale, as we know it 
to-day, is developed directly, in its highly modified form, as 
an outgrowth on the bract (Figs. 1 and 4). The ‘ systematic- 
morphological comparison’ he regards as a very useful factor, 
but the point from which it starts must be clear and certain. 
Eichler started out from the Araucarineae, and Strasburger 
from the Taxineae, hence both from quite different points. 
It is also important not to compare together wrong things. 
Anatomical evidence, taken by itself, is also utterly mislead¬ 
ing, as shown by Van Tieghem’s conclusion that the semi¬ 
niferous scale represents the first leaf of an axillary shoot, 
an idea clearly erroneous when we know that in all Coni- 
ferae the axillary shoot always bears a pair of opposite first 
leaves and never a single leaf. Celakovsky s position on 
this point is, therefore, this, that ‘ the most credible and 
surest method of understanding questionable metamorphosed 
structures, which are apt, owing to heterodox development, 
to be misunderstood, is the metamorphogenesis resting on 
abnormalities, the neglect and wrong estimation of which is 
the [third] cause of the aberrant state of morphology/ 
With the usual insight which he applies to the investiga¬ 
tion of all intricate phenomena of plant-life, the author 
further elucidates for us the true ulterior nature of the parts 
of the seminiferous scale, as also of the sporangial envelopes in 
the various groups of the order. And so well does he account 
for and explain the various structures throughout this large 
and diversified order that, under such skilful unravelling of the 
knot, this diversity becomes a unity, presenting an orderly 
sequence of connected forms such as had never been ex¬ 
hibited, to us in any former treatise on the subject. 
Starting out with the theory, of which he was the first 
