TROPICAL AMERTCAX RUETACE^ 105 



TROPICAL AMERICAN RUBIACE^.— XIII. 

 By H. F. Wernham. 



(Continued from Journ. Bot. 1919, Supplement (Manettia).) 



The Geis'us Coupoui. 



At the end of liis Hisfoire des Planfes de la Ginnne Francohe 

 (1775), Aiiblet adds a sujjplement, and with the expressed purpose of 



inchiding therein " plantes dont on na pu se procurer des 



earaeteres coniplets." The very nature of this an-angenient shoukl 

 inspire a certain confidence in the author's descriptions ; but the result 

 lias been verj^ different, as the sequel shows, in the treatment of the 

 genus Cuupoid, described for the first time on pp. 16, 17 of this 

 sup])lement and figured in plate 377. 



The conspicuous tree ("arbor procera") upon which Aublet 

 founded this new genus was general^ familiar enough localh^a centurv 

 ago to have a name in the Caribbean vernacular — Cowpoui-Bann ; 

 the first pai-t of this Aublet adopted for the generic name. He 

 describes the vegetative parts— form, branches, wood, bark, and 

 leaves — with the care with which so manj^ of his genera were founded 

 and have borne the test of subsequent research. The flowers, he tells 

 us, he has never seen— "je ne Fai point vu en fleur." The' fruit he 

 describes in detail, in Latin and in French : — " sa forme approchoit de 

 celle d'un citron .... couronne par cinq lobes du calice. II ne ren- 

 fermoit qu'une seule amande. II etoit en fruit dans le mois de Mai." 

 Aublet found it growing on the banks of the Galibi river, and so he 

 named the species C. aquatica. He offers no suggestion as to its 

 affinities, generic or otherwise. 



It was left to John Miers to associate flowers with this plant, 

 more than a centur}^ later. Miers found Aublet's type — consisting of 

 two of the very chai-acteristic leaves, detached— in the National 

 Herbarium ; and he matched them, accurately it would seem, with 

 specimens collected by Martin at the end of the eighteenth century in 

 Guiana, now preserved in the same herbarium." These latter bear 

 leaves and flowers clustered together at the extremity of twigs, all 

 arising apparentlv at one transverse level. 



In his ApocynacpfB of South America (1878) Miers introduces a 

 genus Cujnrana (p. 15). This, he says, " is the Coupoui of Aublet, 

 who figured the plant and unripe fruit "only, which is represented as if 

 crowned with a superior calyx — a mistake originating in the inversion 

 of the detached drupe:' Miers offers no kind of evidence to support 

 the all-important statement that I have italicised ; but, after pointing 

 out that, as a result of this " mistake," most botanists had referred 

 this genus to Myrtace^, he drawls the entirely unwarranted conclusion 

 that *'its true place is unquestionably '^ m Apocynacece, as I have 

 ascertained by flowering specimens of the same plant collected in 

 Cayenne by Martin." 



It is clear that the flowers of this plant were unknown to the 

 leading systematists in the interval between Aublet and Miers ; all 

 accepted the description due to the former. The genus is unnoticed 



