The Fruit and Seeds of Erythrina brucei and the Identity of E. abyssinica

Abstract

The plant later to be named E. brucei was discovered by James Bruce somewhere in the region of Lake Tana in 1770 or 1771. He obtained seeds of what he took to be the same species and, on his return to Europe in 1773, these were among those which, as he describes on p. 59-64 of vol. 5 of his 'Travels', were presented, in a rather confused state, to the King of France while he (Bruce) was sick and thought likely to die in Marseilles. After his return to London, Bruce (Travels 5: 65) published in 1790 a description and plate of his Erythrina under the amharic name 'Kuara' (Plate 3, opposite). Although this plate was wrongly cited by A. Richard in 1847 as E. tomentosa R. Brown ex A. Rich., Schweinfurth in 1868 pointed out that it was not that species but agreed with a flowering specimen collected by Steudner in the Gidda (Dschidda) valley NW. of Magdala. Schweinfurth accordingly described the new species as E. brucei, making the Steudner specimen the basis of his description of the leaves and flowers and using Bruce's plate and description for the fruits and seeds. Meanwhile one or more young plants had grown in Paris from the seed supplied by Bruce and these seem to have been given the garden name Erythrina abyssinica. As such they are mentioned by Lamarck in a note at the end of his treatment of the genus from which it does not appear that he intended to describe the plant as a species nor to differentiate it from other species of Erythrina but merely to mention its existence and that it had 'foliis ternatis latissimis caule aculeato'. It seems probable that this does not constitute valid publication of the binomial under the International Code. However, in 1825 De Candolle took up Lamarck's name and, using shoots obtained from a plant in the garden of the Petit Trianon in Paris grown from Bruce's seeds, described it as fully as possible from this sterile material, stating that it is a 'species non satis nota'. This certainly constitutes valid publication and E. abyssinica Lam. ex DC. is thus the oldest validly published binomial applied to any Ethiopian species of Erythrina, though antedated by the 'nomen nudum' E. tomentosa R. Brown. In 1846 Hochstetter described Chirocalyx tomentosus from a sheet of Schimper (1842) 531 and Ch. abyssinicus from another Schimper specimen collected near Djeladjeranne. In his choice of epithets Hochstetter followed Steudel who had previously identified these Schimper specimens as E. tomentosa R. Br. and E. abyssinica Lam. but with doubt, having seen neither Brown's plant nor Lamarck's. In 1847 A. Richard, independently of Hochstetter, described another sheet of Schimper (1842) 531 as E. tomentosa and a Quartin Dillon specimen collected at Add'erbati as E. abyssinica. Richard also expressed doubt about the identity of E. abyssinica Lam. with his plant but he had seen a sterile specimen from the Jardin des Plantes in Paris labelled E. abyssinica which added weight to his identification. Botanists are now agreed that both Hochstetter's and Richard's names all apply to tomentose and glabrescent forms of one and the same species and that this is distinct from E. brucei. But there has been no agreement as to whether it is conspecific with E. abyssinica Lam. On the one hand the shape of the leaflets