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without leaving any central placenta behind. This arises from the style 
originating, in reality, in all cases from the base of the carpels, as it manifestly 
does in Boraginacese and Labiatse. Tliirdly, in the case of Hydrophyllaceae, 
in which the nucamentaceous character gives way, a gyrate inflorescence points 
out the connection between these plants and Boraginaceae. No mistake as to 
this character can be made, unless in regard to Hydroleacese ; but that order 
has several styles, and therefore has fruit composed of more cai'pels than two. 
Alliance I. PHACELIALES. 
Essential Character. — Fruit capsular. Inflorescence gyrate. 
Distinguished from Echiales by the capsular nature of the fruit, but united 
with them, by the greater part of the other characters. 
Order CCI. HYDROPHYLLACE^. The Waterleaf Tribe. 
R. Brown. Prodr. 1.492. (1810); without a name. — HydrophyllEjE, Von Martins N. G. 
et Sp. 2. 138. (1828) ; Link. Handb. 1. 570. (1829), a § o/ Cordiacese ; Bentham in 
Linn. Trans. 17. 267. (1834). 
Essential Character. — Calyx inferior, persistent, deeply 5-cleft ; the recesses usu- 
ally augmented with reflexed appendages. Corolla mouopetalous, hypogynous, regular, 
shortly 5 -cleft, between campanulate and rotate, rarely funnel-shaped. Stamens 5, epipe- 
talous, alternate with the segments of the corolla, inflected in aestivation ; anthers versa- 
tile, 2-celled, the cells parallel dehiscing longitudinally. Ovary superior, simple, 1- 
celled ; style long, 2-cleft ; stigmas 2, terminal ; placenta 2, free at their back or united to 
the shell of the ovary, with two or many ovules on their inner face. Fruit capsular, 2- 
valved, sometimes 1 -celled, with a large placenta filling the capsule, sometimes somewhat 
2-celled, with the dissepiments incomplete. Seeds reticulated ; albumen abundant, cartila- 
ginous ; embryo conical with its radicle next the hilum. — American herbaceous plants, 
hispid like Boraginaceae. Leaves usually lobed, alternate, or the lower ones opposite. 
Flowers arranged in gyrate racemes or unilateral spikes, or occasionally solitary and stalked 
in the axils of the leaves. Bentham. 
Affinities. Very near Boraginaceae and the orders which have been 
recently separated from it, with which Hydrophyllaceae agree in the roughness 
of their leaves and many other marks of obvious resemblance. They are, 
however, known by their undivided 1 -celled ovary, terminal style or styles, 
and ovules (if definite) attached to two stalked fungous placentae, which arise 
from the base of the cell, having their ovules on their inner face, or (if indefi- 
nite) attached to parietal placentae. They are further characterised by the 
presence, at the base of each lobe of the corolla, of 2 scales or lamellae the 
nature of which is unknown. The former mode of placentation is highly 
curious, and, as far as I know, unlike that of any other plants. Many 
Polemoniaceae have very much the habit of Hydrophyllaceae. Bentham, who 
has recently re-examined this order, has the following remarks. 
“ I have never observed in Hydrophylleae any trace of those corolline 
appendages, or squamae, which may be termed laminal, from their position at 
the base of the limb of many infundibuliform corollae, whether monopetalous 
(as Borragineae) or polypetalous (as Caryophylleae) ; but the unguicular or 
tubal squamae are often remarkably prominent. These squamae are analogous 
to those placed at the base of the tube of many Borragineae (having at the 
same time ligular squamae at the mouth of the tube) and to the annulus of 
hairs or scales in the tube of many Labiatae. The laminal squamae are evidently 
