SOUTH AMERICAN BOTANY. 23 
cated æstivation of its border, but they differ from all these 
families, by having a two-celled ovarium, with a solitary ovule 
suspended from the summit of each cell, and in having a nearly 
straight embryo, with superior radicle. The approach to Nolanacee 
is more evident, by their being in like manner prostrate or strag- 
gling succulent plants, growing in saline moist places, by their 
geminate, spathulate, fleshy leaves, with expanded petioles, one of 
which is always inserted laterally a little higher than the other 
upon the stem, to the salient angle of which one of their edges 
is generally decursively continuous ; they have also a solitary 
flower at the origin of each petiole. They differ, however, from 
that order, in having a single two-celled pistillum, not distinct 
ovaria, for Nolana, and most of its congeners, have always several 
distinct gynobasic carpels, generally one-celled, but some of these 
are often united without regularity into two or many-celled nuts, 
which, in such cases, never present more than a single ovule in 
each cell. Grabowskya, which I have referred with some hesita- 
tion to Nolanacee, but which probably represents the type of a 
distinct suborder, exhibits a similar tendency to form spines at 
the axils, and presents also a single pistillum, terminated by a 
lengthened style, and two two-celled nuts, each with a solitary 
ovule, but here, as in the true Nolanea, the embryo is nearly 
annular, with the radicle pointing to the basal hilum. The group 
of plants in question appears to differ from Nolanacee, exactly as 
the Myoparacee are held distinct from Verbenacee; viz., by 
having a somewhat bilabiate corolla, and a superior, instead of an 
inferior, radicle. From the Serophulariacee they are distinguished _ 7 
by a very different æstivation of their corolla, and more particu- — — 
larly by a totally different structure of the ovarium and seed, in 
which latter respect they also differ from the So/anacez, notwith- 
. Standing that they much resemble this order in the shape and —— 
æstivation of the corolla. They certainly approach, in many 
respects, to the JMyoporacee, (especially through Disoon and — 
Nesogenes with their bi-locular, l-ovulate ovaria), with which — 
Order they agree, in their somewhat bilabiate corolla, and in 
having suspended ovules and albuminous seeds with a straight 
