58 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM, 
include specimens in which one of the inner petals is abnormally enlarged and 
is wedged between two of the outer petals, as shown in plate 36. 
EXPLANATION OF PLATES 35-37,—P1. 35, photograph of type plant taken in the field 
by P. G. Russell, of the U. S. National Herbarium. PI. 36, flowers. a, Unopened bud; 
b, nearly mature normal bud with one petal removed, showing details; c, bud, showing 
abnormally enlarged inner petal forcing itself between two outer petals; a, b, c, scale 5. 
Pl. 37, branches, leaves, and solitary flowers. Natural size, 
PLANTS ORIGINALLY DESCRIBED UNDER ANNONA BUT GENER- 
ICALLY DISTINCT. 
ROLLINIA, DUGUETIA, AND RAIMONDIA, GENERA ALREADY 
ESTABLISHED. 
Among the plants originally described under the generic name 
Annona several were found to differ so radically from the type of 
that genus that it became necessary to place them in distinct genera. 
Among the related genera are Rollinia and Duguetia, established 
in 1825 by Augustin de St. Hilaire, and Raimondia, recently estab- 
lished by the present author. 
ROLLINIA St. Hil. 
Rollinia was named in honor of the French historian Charles Rollin. Its type 
is Rollinia longifolia St. Hil. discovered by St. Hilaire on the Lagoa de Fretas, 
near Rio de Janeiro (pl. 38). The plants included in this genus do not differ 
trom those of Annona in their essential parts nor in their fruits, but they have 
a peculiar gamopetalous corolla, the parts of which corresponding to the outer 
petals of the Annonas are developed into three obtuse wings or spurs, which 
leave only a very small-opening above the essential parts. This genus includes 
the following species, originally referred to Annona. 
Rollinia mucosa (Jacq.) Baill. 
Anona mucosa Jacq. Obs. Bot, 16. 1764, excel. syn, Rumph. 
Anona obtusiflora De Tussac, Fl. Antill. 1: 191. pl. 28. 1808, 
Rollinia sieberi A. DC. Mém. Soc, Phys. Hist. Nat. Genéve 5: 199. 1832. 
Rollinia mucosa Baill. Adansonia 8: 268. 1868. 
A small tree with the habit of Annona reticulata L.; young branches puberu- 
lous, at length glabrate, dark brown, longitudinally plicate with inconspicuous 
lighter brown lenticels; leaves ovate-oblong, acute or acuminate at the apex 
or sometimes obtuse, rounded or acute at the base, usually 12.5 to 15 cm. long 
and 5 to 6.5 cm. broad, at first sparsely pubescent above and fulvous sericeous 
pilose beneath, at length glabrate above except along the impressed midrib 
and lateral nerves (about 14 on each side), these pilose above and more 
densely so beneath with appressed rufous hairs; petioles 5 to 10 mm. long, 
grooved above, clothed with rufous hairs when young, at length glabrate or 
nearly so; smaller and relatively broader obtuse ovate leaves near the base of 
the flowering branches; peduncles solitary, extra-axillary, usually opposite a 
leaf, 1-flowered, 2 to 38 cm. long, clothed with minute appressed rufous hairs 
C 
'TI, Bras. Merid. 1: 29. pl. 5. 1825, 
