|
(Last Modified On 1/17/2013)
|
|
|
|
(Last Modified On 1/17/2013)
|
|
Genus
|
BROSIMUM Sw.
|
|
PlaceOfPublication
|
Prodr. Veg. Ind. Occ. 12. 1788, nom. conserv.
|
|
Synonym
|
Alicastrum P. Br. Hist. Jam. 372. 1756, nom. rejic. Piratinera Aubl. Hist. P1. Guian. Fr. 2:888. 1775, nom. rejic. Galactodendrum Humb. Relat. Hist. 2:108. 1819. Brosimopsis S. Moore, in Trans. Linn. Soc. 2 ser. 4:473. 1895.
|
|
Description
|
Monoecious or perhaps occasionally dioecious trees. Leaves alternate, dis- tichous; stipules lateral to fully amplexicaul. Inflorescences globular to turbinate, typically monoecious with 1-2 central pistillate flowers surrounded by numerous minute staminate commingled with more or less conspicuous peltate bracts, but infrequently dioecious. Pistillate flowers: epigynous, the perianth vestigial, the stigma deeply 2-lobed and apparently proterogynous. Staminate flowers with a definite 4-lobed perianth or the perianth vestigial or lacking; stamens 4, 2 or 1, the anthers oblongoid and basifixed to circular and peltate, dehiscing longitudinally to circumscissilly. Fruit a false drupe.
|
|
Habit
|
trees
|
|
Distribution
|
Probably about 24 species ranging from southern Mexico to Argentina, and in the Antilles.
|
|
Note
|
A genus most interesting in its floral modifications and very badly in need of revision, as are most Moraceae. The first three species of the enumeration which follows would be referable to Brosimopsis if a narrow generic concept were followed consistently in this treatment. I have indicated in a previous paragraph that I am not in sympathy with such a view and follow it in other instances merely in deference to previously established custom. In this case, however, custom is not greatly involved. Amongst the Panamanian genera of Moraceae alone no less than four parallel reductions of the male flowers to a vestigial perianth and a single stamen may be observed: Trophis (Sorocea) -* Clarisia; Brosimopsis -> Brosirnum; Perebea Castilla; Olmedia Pseudolmedia. The eight Panamanian species also show a most interesting transition in the structure of the anther from a rather commonplace basifixed type with longitudinal dehiscence to a most unusual peltate body with perfectly symmetrical circumscissile dehiscence, aptly described by Aublet (loc. cit. sub Piratinera) as "en forme de champignons". The series is illustrated in the accompanying figures. In the following text two new Costa Rican species are described, since they have been collected only a few miles from the Panamanian border and probably will yet be discovered in our flora.
|
|
Key
|
a. Flowers not wholly concealed before anthesis by the weakly expanded, long-stipitate peltate bracts, with a conspicuous perianth and 2-4 stamens with oblongoid basifixed anthers; heads globose; stipules lateral, their scars about half-surrounding the stem (except B. allenii). b. Stipules lateral; leaves membranaceous, oblong to obovate-oblong; flowering peduncles slender, almost as long as the rather small and delicate heads or somewhat longer; flowers with essentially equal tepals and 2-4 stamens. c. Leaves relatively large, 2- to 3-times as long as broad, glabrous; anthers setose-appendiculate; fruits relatively large, the seed about 2 cm. long ......-...,... 1. B. OJOCHE cc. Leaves relatively small, 3- to 4-times as long as broad, softly white-tomentellous beneath; anthers exappendiculate; fruits rela- tively small, the seed about 1 cm. long.-..,.,,,................,.,.,.,.,,,.2. B. COSTARICANUM bb. Stipules almost fully amplexicaul, their scars almost completely sur- rounding the stem; leaves rather heavily coriaceous, ovate-elliptic; flowering peduncles stout, much shorter than the massive heads; flowers with strongly unequal tepals and 2 stamens -... ........... 3. B. ALLENII aa. Flowers wholly concealed before anthesis by the strongly expanded, shortly stipitate peltate bracts, with a vestigial or obsolete perianth and 1 stamen with a nearly circular anther; stipules almost fully amplex- icaul, their scars nearly surrounding the stem (except B. guianense). b. Stipules lateral, about 3-5 mm. long; heads obconic or turbinate. - 4. B. GUIANENSE bb. Stipules almost fully amplexicaul; heads globose. This content downloaded on Mon, 14 Jan 2013 11:55:03 AMAll use subject to JSTOR Terms and Conditions[VOL. 47 126 ANNALS OF THE MISSOURI BOTANICAL GARDEN c. Stipules 1.5-3.0 cm. long; flowering peduncles stout; anthers obliquely inserted on the filament, clearly longitudinal in dehis- cence .-., . . . . . . . . , , . . , . . , .. ......................... 5. B. UTILE cc. Stipules 5-10 mm. long; flowering peduncles slender; anthers peltately inserted on the filament, circumscissile in dehiscence or falsely so. d. Anthers excentrically peltate, dehiscing by 2 basal valves; leaves elliptic-obovate. ................................ 6. B. BERNADETTEAE dd. Anthers centrally peltate, dehiscing circumscissilly. e. Leaves oval to oblong-elliptic, obtuse to shortly subcuspidate- acuminate; peduncles about as long as the flowering heads to somewhat shorter-. .................-...-................ ..... 7. B. ALICASTRUM ee. Leaves broadly ovate to oblong-ovate, narrowly subcaudate- acuminate; peduncles much longer than the flowering heads. 8. B. TERRABANUM
|
|
Tag
|
|
|
|
Project Name
|
|
Tag
|
|
|
|