488 DISCIFLORZ.—LINACE#. 
Placentas in the axis. 
Styles distinct to the base. 
Calyx much imbricate, in an irregular 
broken whorl, 
Petals small, sessile . : d . Llatinacer. 
Calyx but little imbricate, in a com- 
plete whorl. 
Petals minute . : : . . Paronychiaceex. 
Calyx valvate : : : . Tiliacex. 
Styles more or less combined. 
Calyx much imbricate, in an irregular 
broken whorl. 
Flowers surrounded by an involucre. Chlenacex. 
Calyx but little imbricate, in a com- 
plete whorl. 
Sepal spurred . : : : . Vochysiacee. 
Calyx valvate. 
Stamens united by their filaments into 
a column, : . Sterculiacee. 
Stamens not united intoacolumn . Tiliacex. 
In order to prevent the student being misled, and thus to refer plants 
to their wrong positions in the Vegetable Kingdom, it should be particularly 
noticed, that although the general character of the Thalamiflore is to have 
dichlamydeous flowers and polypetalous corollas, yet exceptions do occur 
occasionally to both these characters. Thus, we find apetalous genera and 
species in Ranunculacee, Magnoliacexe, Berberidacex, Sarraceniacex, Meni- 
spermacee, Papaveracee, Crucifere, Canellacex, Bixacew, Violacex, Caryo- 
phyllacee, Paronychiacew, Scleranthacew, Malvacew, Sterculiacew, and 
Tiliacex. 
Again, in the orders Anonacex. Pittosporacex, Polygalacex, Portulacaceex, 
Tamaricacex, Ternstremiacee; Rutacew, and Dipteraceew, we find some 
monopetalous species and genera. 
In Dilleniacew, Papaveracex, Cupparidacee, Resedacex, Violacex, Caryo- 
phyllacexw, Portulacacew, Malvacee, and Sterculiaez, some of the species 
have stamens more or less perigynous instead of hypogynous. Again, in 
some orders, as in certain Ranunculacew, Calycanthacew, Anonacex, 
Nympheacee. Portulacacex, Capparidacex, Polygalacex, Bixacex, Tern- 
stremiacee, Vochysiacex, Tiliacewx, and Dipteracex, the calyx is more or 
less superior. 
Series 2. Discifloree. 
Cohort 1. Geraniales.—Calyx generally imbricate, or rarely 
valvate. Gyncecium usually syncarpous, or sometimes 
apocarpous ; ovules suspended ; raphe ventral. Seeds albu- 
. minous or exalbuminous. 
Order 1. Linace#,the Flax Order.—Character.—Herbs 
or rarely shrubs. Leaves alternate, opposite, or rarely verti- 
cillate, simple, entire, exstipulate, or rarely stipulate. Inflor- 
escence cymose. Flowers regular (jig. 924), symmetrical, 
generally very showy. Calyx imbricate, with 3, 4, or 5 sepals 
( fig. 924), persistent. Petals 4—5 (fig. 924), unguiculate, very 
deciduous, twisted in eestivation. Stamens 4—5, united at the 
base so as to form an hypogynous ring (jig. 925), from which 
