PITTIER—-PLANTS FROM COLOMBIA AND CENTRAL AMERICA. 24] 
The 9 types are sufficiently well characterized, to my mind, to be 
considered as so many distinct species. For those, however, who may 
object to an extreme division, they may be reduced to six, as follows: 
. C. sambuense Pittier. 
. C. superbum Pittier. 
. C. farinosum HH. B. K. 
. C. argenteum, with C. phaenopetalum and C. polystachyum as subspecies. 
C. erianthuwm Benth. 
6. C. benthamianum, with C. lepidopetalum as a subspecies. 
The following character is for the Central American and Mexican 
species only. 
he 
bo 
CH me OO 
Combretum, section Micropetalae Engl. & Diels in Engl. Monogr, Afrik. 
Pflanzenfam. 3: 10. 1899. 
Flowers tetramerous. Calyx funnelform or turbinate-campanulate. Petals 
small, equal to the lobes or shorter. Stamens 8, much exceeding the calyx, the 
filaments erect, the anthers ovate or oblong. Disc adnate to the calyx, the 
margin free and more or less hairy. Ovary ovate or fusiform, more or less 
stipitate. Fruit a 4-winged samara. 
Vines or shrubs, the leaves and inflorescences more or less covered with 
white or brown scales, the leaves opposite, the inflorescence usually terminal, 
paniculate, once branched or rarely twice branched, the flowers usually secund 
in the spikes. 
KEY TO THE SPECIES. 
Leaves large for the section, 15 cm. long and up to 9.5 cm. 
broad ; flowers also large, about 2 cm. long, including 
the ovary_------------ -- ~------ e+ 1, C. sambuense. 
Leaves 4 to 14 cm. long or longer, but always narrower 
than in the preceding; flowers not over 1.5 cm. long. 
Panicles twice branched__-------------------------. 2. C. superbum. 
Panicles once branched. 
Petals oblong-spatulate, 2 mm. long, 0.8 to 1 cm. 
broad. Anthers oblong____-------------- 3. C. farinosum. 
Petals of broader forms. 
Petals ovate. 
Calyx funnelform, narrow, sparsely villous 
within; margin of the disc sparsely 
villous__.___------------------------ 4. CO. phaenopetalum. 
Calyx turbinate-campanulate, densely scaly 
without; margin of the disc densely 
long-villous. 
Panicles up to 45 cm. long, with 6 to 8 
pairs of spikes; petals glabrous___ 5. C. polystachyum. 
Panicles short, sparsely branched ; petals 
minutely pilosulous without_____- 6. C. argenteum. 
Petals suborbicular. 
Calyx villous-tomentose without_____----~-. 7. CO. erianthum. 
Calyx sealy without. 
Petals scaly, shorter than the calyx lobes_ 8. C. lepidopetalum. 
Petals glabrous, equaling the calyx 
lobes______-------------------------- 9. C. benthamianum. 
