Page:Journal of botany, British and foreign, Volume 34 (1896).djvu/52

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86 NEW AFRICAN CONVOLVULACE^. feram ssepe transit, quamquam facile pro specie autonoma censeri potest. Supra rupem ad Souffriere (n. 146) et Bath Estate (n. 141) in Dominica et ad Baleine Falls (n. 295), Lomond Bay et Fort Charlotte (n. 287j in St. Vincent.— Pycnoconidiis cum f. granulifera congruit. (To be continued.) NEW AFEIOAN CONVOLVULACEiE. By a. B. Eendle, M.A., F.L.S. Ipomoea marmorata Britten & Rendle, sp. n. Caule lignoso striato glabro, foliis magnis petiolatis reniformibus vel a basi reni- forme suborbicularibus, margine crispulata apice rotundo vel retuso, facie superiore sparse inferiore in venis venulisque dense albo- tomentosa ; pedunculis brevibus unifloris, floribus magnis, brevius pedicellatis ; sepalis magnis late ovato-oblongis, crassiusculis, glabris, obtusis, rarius retusis ; corolla longe tubulosa superne ampliata, glabra ; antheris et stigmate subgloboso haud exsertis. Hab. Lake Stephanie, Donaldson Smith, May 26, 1895. Herb. Mus. Brit. A striking plant, characterised by its long tubular flowers and large broad leaves, to which the broad protruding tomentose veins give a marbled appearance on the under surface. The petioles are equal to or rather shorter than the length of the blade. The oldest and largest leaf is reniform, with a retuse apex, 2| in. long and 5 in. broad ; the three following are 2^-2 in. long by 3-2| broad, and are rounded above. The short strong peduncle (^ in.) bears a single flower and two lateral alternate bract- scars, the axils of which contain the remains of a bud. The short stout pedicel is 8 lines long. The inner sepals are 1 in. by 8 lines, the two outer slightly shorter. The corolla is 5 in. long, and of uniform diameter (i in.) for about 3| in. ; in the already withering flower the stamens and stigma reach to about this level. Is very near the South African I. alhivenia Don, the leaves of which are similar in shape, and show the striking marbled appear- ance of the lower surface due to the broad densely tomentose veins and vein lets ; it is, however, at once distinguished by its very large calyx, twice the size of that of 7. albivenia; the corolla is also larger, but in less proportion than the calyx. The same distinction separates it from Z. lapidosa Vatke (e descript. in Liiinaa, 43, p. 607), an East Tropical African species, in which moreover the leaves are longer than broad. I, Wakefieldii Baker {Kew Bulletin^ 1894, p. 74), from the Nyika Country, is also closely allied, but the leaves are thinner and tomentose only when young ; while the calyx is again only about half as large as in I. marmorata, and not glabrous. Ipomoea dammarana, sp. n. Erecta, albo-tomentosa, caule rigido lignoso ; foliis mediocribus ovato-orbicularibus, facie inferiore et petiolis velut caule et pedunculis dense, facie superiore sparsius