A Grammatical Dictionary of Botanical Latin

ferrugineus,-a,-um (adj.A), ferruginus,-a,-um (adj.A): ferruginous, the color of iron-rust, dark-red, rusty, light brown with a little mixture of red; the taste of iron; cf. rubiginosus,-a,-um (adj.A): rusty-red;

- S. (composita) magna oblongo sublacunosa e ferrugineo nigra, stromate terreo (S&A), S. composita large, oblong, somewhat lacunose from rust-red a dull black, with the stroma earth-colored.

- in pulverem tandem e sordide ferrugineo subvirescentem, at last into a somewhat greenish from a dirty rust-red dust.

- pulvis subcompactus, vivide aetate sordide ferrugineus, the dust somewhat compacted, brightly [vividly] with age dull rust-red.

- macula sordide ferruginea, the spot dirty rust-red.

- flores et ramuli haud magni, extus ferrugineo-tomentosi (B&H), the flowers and branchlets not large, externally rust-red-tomentose.

- capsula crassa, 3-loba, ferrugineo-birsuta (B&H), the capsule thick, 3-lobed, rusty-red-hairy.

- corolla aurantiaco-ferruginea (Boissier), the corolla orange-rusty red.

- foliis subsessilibus subtus subferruginei (DeCandolle), with the leaves somewhat sessile, underneath somewhat rust-red.

- foliis subglabris, junioribus ramisque ferrugineo-velulinis, (DeCandolle), with the leaves somewhat glabrous, the younger leaves and the branches velvery rust-red.

Note: classically ferrugo,-inis (s.f.III) is also "the color of iron rust, dusky (iron grey, dark blue, steel blue) color" (Cassell's).