On the Seedling-Structure of certain Piperales. 
BY 
T. G. HILL, F.LS. 
Lecturer on Biology in the Medical School of St. Thomas's Hospital, London. 
With Plate X and three Diagrams in the Text. 
T HE completion of the investigation, started some time ago 1 , on 
the structure of the seedlings of certain Piperales, has been much 
handicapped by the difficulty experienced in obtaining seeds ; and the 
failure, in many cases, of these, when procured, to germinate. However, 
sufficient material has now been examined to warrant publication. 
The cohort Piperales is of interest, inasmuch as it is characterized 
by certain features shared in common with many Monocotyledons. Thus 
Campbell 2 , comparing certain Araceae with Peperomia , remarks, 4 in the 
form of the leaves and inflorescence, as well as in certain anatomical 
characters, e. g. the distribution of the vascular bundles in the stem of 
Peperomia , there are very curious parallelisms. The structure of the 
flower and position of the ovule are also similar.’ 
In a later paper 3 he further expresses his opinion that ‘the resem- 
blances in general habit, as well as the distribution of the vascular bundles 
in Peperomia and the Araceae, might indicate a remote relationship 
between them ; the presence in the latter of nucellar tissue, which might 
be compared to the perisperm of the Piperaceae, might be cited as further 
evidence of a possible relationship. . . . The possibility of a connexion with 
some of the lower Dicotyledons through forms like Peperomia may fairly 
be considered worthy of consideration.’ 
And further, in writing of Peperomia 4 , our author makes the following 
statement : ‘ From a study of many low types among the Monocotyledons, 
which cannot be readily derived from higher types, e. g. Naias } many 
Araceae, it seems more reasonable to consider the single carpel with 
1 Hill, T. G. New Phytologist, Vol. iii, February, 1904. 
8 Campbell, D. H. Studies on the Araceae, L Ann. Bot., xiv, 1900, p. 22. 
8 ,, ,, Studies on the Araceae, III. Ann. Bot., xix, 1905. 
4 „ „ The Embryo-sac of Peperomia. Ann. Bot., xv, 1901. 
[Annals of Botany, Vol. XX. No. LXXVIII. April, 1906.] 
