STUDIES IN SAXIFRAGA. III. SAXIFRAGA. SECTION MICRANTHES

Abstract

Perennis caudice breve fibroso caule florifero scapiforme 24-30 cm. alto tota longitudine pilis glanduliferis brevibus dense obsita, folia basalia ascendentia tenua plana 3-1O cm. longa lamina elliptica vel oblonga vel ovatooblonga plus minusve remote dentata vel denticulata in petiolum longum sensim contracta, juvenculis infra obscure pubescentibus et margine ciliolatis adultis infra glabris vel subglabris, inflorescentiae rami pauci graciles adscendentes superne abbreviati prophyllis parvis linearibus instructis, flores pauci parvi sepala oblonga vel ovato-oblonga vel triangularia obtusa circa I.5-3 mm. longa viridia I-3-nervia in anthesi valde reflexa sparse glanduloso-ciliolata et ebscure et irregulariter denticulata, petala alba parva sepalis subaequilonga vel longiora circa 2-3 mm. longa obtusa retusa late unguiculata uninervia nervo medio i-2-ramoso, stamina filamenta clavata sepalis petalisque subaequilonga antherae rubiginosae, carpidia dua distincta circa 4-5 mm. longa ovariis hypanthio ad medium longitudinis adnatiis disco valde lobato instructiis in stilos crassos divergentes subito contractis stigmatibus discoideis. Fructum non vidi. Plants perennial from a short fibrous oblique caudex; flowering stems 24-30 cm. high, densely glandular pubescent with short hairs throughout its entire length, branching above into an open, rather few-flowered cymose paniculate inflorescence of a very few slender spreading ascending branches which are much shortened upwards, -are subtended by small linear bracts. and terminate in small, loose, mostly 2-3-flowered, glomerules. Leaves basal, ascending-spreading up to io cm. long, flat and mostly very thin, the blades elliptic to oblong or ovate-oblong, obtuse, mostly remotely and shallowly dentate to serrate-dentate, or denticulate, when young glandular ciliolate and obscurely glandular pubescent beneath but becoming glabrous or nearly so with age, all tapering more or less gradually into a long thin flat, basally sheathing, petiole. Flowers small; sepals broadly to narrowly oblong-ovate or oblong, more or less obscurely denticulate, and very sparsely or scatteringly minutely glandular ciliolate, green and strongly reflexed at anthesis; petals small, up to 3 mm., white, about equalling or sometimes exceeding the sepals, but frequently varying considerably in size in the same flower, long, elliptic to elliptic-ovate, more or less rounded and notched at the apex and tapering abruptly into a broad claw at the base, the solitary midrib frequently with one or two short ascending lateral branches from the middle region; stamens Io, slightly exceeding the sepals at anthesis but elongating with age, the anthers deep to pale rose-red, becoming whitish with age, introrse, the filaments clavate but appearing subulate with age; carpels 2, distinct, up to 5 mm. in length; ovaries deeply adnate to the turbinate receptacle and expanded into a rather strongly but irregularly lobed gland immediately above the insertion of the stamens, and strongly contracted upwards into rather