0 ON. 
PREFACE. xiii 
curious fact that the fibres of the former are always 
punctate; while those of the latter, are not: it is these 
only which are truly fibrous, the former being elon- 
gated cells. "These true fibres exist in Piper either in 
distinct fascicles when they are contiguous to the 
fibro-vascular, from which they are always separated by 
soft cellular tissue, and they are always situated to- — 
wards the circumference of the stem, or they form a 
continuous zone close to the bark. 
This, in the genus under consideration is waxy, 
the latter formed fibro-vascular fascicles occupying the - 
concavities; the convexities corresponding to the | 
green lines so conspicuously visible in many species 
under the cellular integuments. 
Podoslemea.—From an examination of two species 
of Podostemon, I incline to the opinion of their be- 
ing monocotyledonous, and that they are especiglly 
related to Lemna and Pistia. I have not however 
ascertained the existence of a foramen in the ovula, 
nor have Í yet seen ripe seeds. From the invaribly 
lateral situation of the stamina, and from the presence 
of abortive filamentose ones on the column formed by 
the cohesion of the filaments, I incline to think that 
the flowers are monecious. In this genus a binary 
arrangement is strictly followed even in the formation 
of the pollen. One of the most striking features in - 
this genus is its evascularity and in cni axis of in- 
florescence being totally distinct. Dekoro, te: ‘18th 
-. Since sees above was written 1 o ai 
l , its seeds are euulbir 
