H. F. Wernham. 
76 
structure, moreover, such as the presence of perisperm and the 
number of nuclei in the developing embryo-sac, 1 have been advanced 
in support of the primitiveness of these piperaceous forms. 
Apart from a general objection to the primitiveness of a solitary 
sporangium, to be referred to later, it is pointed out in the case of 
the Piperaceas, that the species which comprise this natural order 
display considerable variety in the number of their floral parts. In 
the androecium, we meet with the numbers 2, 3, and 6—co ; in the 
gynsecium, the ovary is crowned in some cases by two or more 
styles, indicating the presence of more than one carpel,—a condition 
comparable with that which obtains in Najas. In the allied natural 
order, the Saururaceae, moreover, a more or less indefinite number 
of stamens is associated with 3 to 5 subapocarpous carpels, and in 
cases where the ovary is unilocular, several ovules may be present. 
And lastly, in Saururaceae, and in an allied group, the Chloranthaceae, 2 
the ovary is sometimes inferior. 
This variability within a close circle of affinity leaves the 
question an open one, on general grounds, as to whether the 
solitary or the aggregated state of the sporangia be relatively 
primitive. 
But broader considerations seem to outweigh the evidence 
afforded by minor detail. We meet with no cases of solitary 
sporangia in the reproductive organs of Vascular Cryptogams, 3 and 
the solitary condition is decidedly the exception in the Gymnosperms. 
The higher reproductive units—strobili, sori, cones—and their 
general occurrence throughout these last-named groups, all point 
to aggregation of sporophylls and sporangia as a condition firmly 
established before the advent of the Vascular Cryptogams in the 
course of the evolution of plant forms. 
Again, the solitary ovule is frequently, if not prevailingly, 
shared between two or more sporophylls, 4 and the component 
carpels are fused together to form the unilocular ovary. We can 
suggest no parallel to either of these conditions outside the Angio- 
sperms; and this fact would appear to weigh not inconsiderably 
1 See Johnson. “ On the Development of certain Piperaceae.” 
Hot. Gaz., xxxiv, 321, 1902 ; also 
Brown. “ The Nature of the Embryo Sac of Peperomia." Bot. 
Gaz. xlvi, 445, 1908, where the relative literature is cited. 
2 See Armour, in The New Phytologist, vol. V., p. 49: “On 
the Morphology of Chloranthus. 
3 The female sporocarp of Azolla seems to afford the single 
exception to this statement. 
Supra, p. 75, 
4 
