| HABIT: C. nutans is a perennial herb which can grow up to 1 m tall with pubescent branches and cylindrical, striate, and glabrescent stems. |
| LEAVES: The leaves are simple, opposite, narrowly elliptic-oblong or lanceolate (2.5–13.0 cm long × 0.5–1.5 cm wide). |
| STEM: This shrub is about 1 m tall, and stems cylindrical, striate and glabrescent. The petiole is 0.3–2.0 cm, sulcate, bifariously pubescent and leaf blade lanceolate-ovate, lanceolate or linear-lanceolate. |
| LEAVES : The leaves are apex acute or acuminate and exsculptate; dentate or subentine margins. Both surfaces of leaves are pubescent when young then glabrescent. The leaf base are cuncate, obtuse rounded or truncate; often oblique. Petiole is 3–15 mm long. |
| FLOWERS: The flowers are sordidly yellow or greenish yellow and dense cymes at the top of branches and branchlets; always covered with 5-alpha cymules . The calyx of flower about 1 cm long with grandular-pubescent. Corolla is dull red with green base, about 3.0–4.2 cm. The stamen is exerted from the throat of corolla. The ovary is compressed into two cells and each cell has two ovules. The styles are filiform with shortly bidentate. |
| FRUIT: Capsule is oblong basally wrapped into 4-seeded short stalk. |
