HE TEROCHLAMYDEAE 
93 
with 4 appressed segments ; outer segments smaller and darker ; inner segments obovate-mucronate, 
about one-third to one-fourth as long as the calyx-tube. Calyx faintly veined ; tube cylindrical, about 
i '5 — 2’ocm. long and 4mm. broad; segments broadly triangular, about 4 mm. long. Petals rose or 
white, toothed, contiguous or nearly so. Capsule broadly cylindrical. Seeds strongly punctate. 
Not indigenous ; walls of Rochester Castle, Kent. 
France, Spain, Italy, south-eastern Europe. Naturalised in many other parts of temperate Europe. 
Subclass 4. HETEROCHLAMYDEAE 
Heterochlamydeae Moss in Carter Gen. Brit. Plants 45 (1913); Cambr. Brit. FI. ii, 3 (1914); Grove 
Syn. Fain. Brit. Plants 17(1915); Dicotyledoneae Bd Engler Syll. ed. 2, 1 1 5 (1898). 
Inflorescence cymose or racemose, rarely solitary. Flowers usually monoclinous, usually cyclic, 
sometimes spiral (as in some of the more primitive forms). Perianth usually dichlamydeous and 
heterochlamydeous, rarely (as in some of the more primitive forms and also in reduced forms) 
monochlamydeous ; if dichlamydeous, corolla usually polypetalous (but cf. Cotyledon) ; if monochlamy- 
deous, either petaloid (usually in the primitive forms) or sepaloid (usually in the reduced forms) ; 
rarely absent. Pollination usually entomophilous, less often (and usually in the reduced forms) ane- 
mophilous or antophilous. Stamens few or many. Ovary usually syncarpous, less often (as in the 
more primitive forms) apocarpous or syncarpous only at the base. Fertilisation porogamous or very 
rarely (as in Alchemilla ) mesogamous. Seeds usually not campylotropous, sometimes produced apo- 
gamously (e.g., in Alchemilla spp.). Integument of seed double or single. 
There is at present no very satisfactory classification to offer of the sub-class Heterochlamydeae. The difficulties of 
classifying the group are to a great extent inherent, and due to the following causes. The number of species, genera, and 
families of the sub-class is very great ; and whilst the general characters of these groups are fairly well known, yet the gaps 
between many of them are very small ; and even when this is not so there is often inadequate knowledge of the develop- 
ment and systematic value of the separating characters. What to the ordinary eye may seem an identical character, e.g., an 
indefinite number of stamens, may arise in various ways ; and it is often the development of such a character and the 
interpretation placed upon that which determine whether the character be regarded as primitive or derived ; and upon that 
conclusion may depend the place accorded in a modern system of classification to a given group of plants. 
Unless the following orders and groups of orders are closely studied from the point of view of their genetical relation- 
ships to one another, and unless an attempt is made to trace the various evolutionary tendencies within the limits of each 
group, the significance of the classification here adopted (following Engler’s Syllabus) cannot be understood. It will tend to 
a more correct apperception of the arrangement if it is supposed that, in general, groups of equivalent value have arisen 
from a common stock, and that it is therefore the case that the more primitive members of the different equivalent groups 
are frequently more closely allied to each other than the more primitive members of a given group to the more specialised 
members of that group. 
For characters of the Heterochlamydeae, see also Volume 11, page 3. For subclass 1 ( Amen - 
tiflorae ), see Volume 11, page 2 and page 3. For subclass 2 ( Petaloideae ), see Volume 11, page 2 
and page 103. For subclass 3 {Centrospermae ), see Volume 11, page 2 and page 150. 
British orders of Heterochlamydeae 
(a) Order with prevailing hypogyny and apocarpy 
Order 1. Ranunculales (or Ranales ) (p. 95). Receptacle usually more or less convex. In- 
florescence usually cymose or solitary. Flowers spiral to hemicyclic and cyclic, monochlamydeous 
(the primitive condition) to heterochlamydeous, usually actinomorphic, rarely zygomorphic, hypogynous 
to hemi-epigynous and epigynous. Stamens usually 00 . Carpels co to 1, free from the other parts 
of the flower, and usually apocarpous. Integuments of the seed 1 or 2. 
The more primitive members of the order have a definite inflorescence, a convex receptacle with the parts of the flower 
placed upon it, monochlamydeous and hypogynous flowers with numerous free stamens and carpels arranged spirally. 
Specialisation can be traced in the reduction of the inflorescence, in the receptacle becoming somewhat concave, in the 
transitions from the spiral to the cyclic arrangement of the parts of the flower, in the development of a corolla from 
stamens to “ nectar-leaves ” or staminodes and ultimately to petals, in the reduction of the number of the members of the 
androecium and gynoecium, and rarely in the cohesion of the carpels, or the adhesion of carpels and calyx giving rise to 
the hemi-epigynous condition. The order is closely related to the more primitive members of the Rosales and Hypericales. 
0 ) Order with prevailing hypogyny and syncarpy 
Order 2. Papaverales (or Rhoeadales) (p. 156). Leaves spiral, exstipulate. Inflorescence 
usually racemose or solitary. Flowers usually cyclic, the androecium occasionally remaining spiral, 
