80 THE JOURNAL OP BOTANY 



island, together with the figure of a second species, C. Humblotii, 

 wliich is distinguished by its long oblong leaves and 4-merous 

 flowers ; unfortunately, however, no description of this second 

 species is given. 



A third species — also 4-merous — was described by Augustine 

 De Candolle from material collected by Mocquerys (no. 142) in the 

 Maroa district. This is C. maroana, of which the author states 

 that " Le C. Humhlotii doit etre tres voisin du notre. II en differe 

 cependant par la forme du limbe." 



This being so, the additional species now described appear to 

 be quite distinct. The five species fall conveniently into the clavis 

 exhibited below. The leaf-shape, characteristic as it is, seems to 

 afford the best preliminary guide towards identification : — - 



Flowers 5-merous, leaves broadly elliptical, mostly 5-6 cm. long 



1. G. madagascariensis. 

 Flowers 4-merous, leaves nearly always more than 7 cm. long. 

 Leaves rounded at the base, subsessile . . 2. C maroana. 

 Leaves acute at the base. 



Leaves narrow-lanceolate, leathery . 8. C. angustifolia. 



Leaves broadly elliptical, submembranous 4. G. Gouclotii. 



Leaves long-oblong . . . . 5. C Humhlotii. 



Descriptions of these five species are given below ; that of the 



first, upon which the genus was founded, has been revised. 



1. C. MADAGASCARIENSIS Gmelin Syst. 372 (1791), nomen. 



G. axillaris Willd. Sp. PI. 976 (1797). 



Frutex omnino glaber, ramulis subteretibus nodosis, foliis 

 coriaceis nitidis ellipticis apice obtusis basin versus in petiolum 

 brevem plus minus subito angustatis, stipuhs triangularibus cuspi- 

 datis, inflorescentiis ssepissime 3-4-floris, floribus subsessilibus, 

 calyce campanulato 5-dentato dentibus late triangularibus, corolla 

 campanulata lobis 5 oblongis apice spathulatis quam tubus brevi- 

 oribus utrinque glaberrima, staniinibus 5 subsessilibus antheris 

 linearibus obtusiusculis basi lobatis, stylo filiform! stigmate in 

 duobus lobis subaequalibus diviso, bacca. ... 



Hab. Fort Dauphin, Madagascar, Scott Elliot, 2945 ! (Herb. 

 Mus. Brit, and Kew) ; J. Gloisel, 263 ! (in Herb. Mus. Brit.). 



Folia 5-6 (3-5-7-5) cm. long, x 2-7-2-9 (1-5-3-3) lat. Cost® 

 secundariae angulo 70 -"-SO^ ad venam centralem insert®, utrinque 

 6-8 distantes. Stipulae 2 mm. long. Inflorescentias pedicella sub 

 anthesin ca. 1'6 mm. long., ad apicem fere 6 mm. lat. Calyx totus 

 3-5 mm. ; dentes ca. 1 mm. long. Corollse lobi 3 mm., tubus 4 mm. 

 long. Antherge, dimidio exsertse, ad 2-1 mm. long. 



This, the species which has been the longest known, is the 

 only one so far known which has pentamerous flowers. 



2. C. MAROANA Aug. DC. BuU. Herb. Boiss. ser. ii. 1, 1901, 

 p. 584. I have not seen this plant, but the rounded leaf-base is a 

 remarkable feature. The original description is appended: — ■ 



Frutex ramulosus glaber, ramis teretibus, foliis subsessilibus 

 oblongis (8-11 cm. longis, 3^-4 cm. latis) basi rotundatis apice 

 acuminatis subcoriaceis nervis lateralibus 8-10 adscendentibus 



