3. Delphinieæ, Larkspur Group. Zygomorphic flowers with coloured calyx; the 2 posterior petals (honey-leaves) are transformed into nectaries, the others are small or absent altogether.—Aconitum (Monkshood); 5 sepals, of which the posterior one (Fig. [379] A) is helmet-shaped; most frequently 8 petals (as in Fig. [372]), of which the two posterior ones (honey-leaves) are developed into long-clawed nectaries (Fig. [379] A, k) enveloped by the helmet-like sepal; the others are small, or are to some extent suppressed. Stamens on a spiral of 3/8–5/13; generally 3 carpels. Perennial herbs.—Delphinium (Larkspur); very closely allied to Aconitum, but the anterior 4 petals are most frequently wanting, and the 2 posterior ones have each a spur, which is enclosed by the posterior sepal, the latter being also provided with a membranous spur. Stamens and carpels arranged on a spiral of 3/8, 5/13, 8/21. In D. ajacis and consolida there is apparently only 1 petal (by the fusion of 4) and 1 carpel.
Fig. 379.—Aconitum napellus. A Flower in longitudinal section, below are the 2 bracteoles; a half of helmet-like sepal; b and c other sepals; k nectary; f carpels. B Ovary in longitudinal section; C the same transversely; d dorsal suture; v ventral suture.
B. Fruit achenes. Many carpels, each with only 1 ascending (Fig. [373] C), or pendulous (Fig. [373] D), perfect ovule; often also rudimentary ovules above it (Fig. [373] A, B). Fruit achenes.
4. Ranunculeæ, Buttercup Group, has double perianth. Myosurus and Adonis have pendulous ovules as in Anemoneæ (Fig. [373] D); Ranunculus, with Batrachium and Ficaria, erect ovules (Fig. [373] C) and downwardly-turned radicle.—Ranunculus. Most frequently S5, P5, many spirally-placed stamens and carpels (Figs. [371], [380]). The petals (honey-leaves) have a nectary at the base, covered by a small scale. Batrachium, Water Ranunculus, deviates by the achenes being transversely wrinkled; dimorphic leaves. Ficaria has 3 sepals and 7–8 petals arranged in 2/5–3/8. F. ranunculoides (the only species) has tuberous roots, which spring from the base of the axillary buds, and together with these, serve as organs of reproduction. The embryo has only 1 cotyledon.—Myosurus (Mouse-tail) has small prolongations from the 5 sepals; 5 narrow petals which bear the nectaries near the apex; sometimes only 5 stamens, and an ultimately very long receptacle, with numerous spirally-arranged achenes (Fig. [381]).—Adonis is acyclic (Fig. [372]); most frequently 5 sepals with a divergence of 2/5, 8 petals of 3/8, indefinite stamens and carpels of 3/8 or 5/13. The corolla has no nectary.
Fig. 380.—Flower of Ranunculus sceleratus in longitudinal section.
Fig. 381.—Myosurus minimus: c cotyledons; m the foliage-leaves; f the floral axis with the carpels, and g the same without; y insertion of perianth.]
5. Anemoneæ, Anemone Group, has a single perianth. (Pendulous ovules (Fig. [373] D), radicle turned upward).—Anemone has a single, petaloid, most frequently 5–6-leaved perianth, and beneath the flower most frequently an involucre of 3 leaves, placed close together in the form of a whorl. In A. nemorosa, ranunculoides, etc., the involucral leaves resemble foliage-leaves; in A. hepatica they are situated close under the perianth, and resemble sepals, and in the sub-genus Pulsatilla they stand between the foliage-leaves and floral-leaves. The style of Pulsatilla finally grows out in the form of a feather. The main axis of A. hepatica has unlimited growth (it is biaxial), and the flowers are borne laterally in the axils of the scale-leaves; in the others (uniaxial) the flower is terminal, and the rhizome becomes a sympodium after the first flowering.—Thalictrum (Meadow Rue) has no involucre; 4–5-leaved, greenish perianth. The receptacle is flat. The stamens are brightly-coloured and have long filaments; 1–5 accessory flowers may occur in the leaf-axils of the panicle-like inflorescence.