44 Ign. Urban, 



Mentzelia aspera Linn. vor. virescens Anderss. Galap. Veg. (1854) 222; Walp. 

 Ann. V. 5. 



Jlentzelia aspera Linn. var. lobata Anderss. Galap. Veg. (1854) 222; Walp. 

 Ann. V. 5. 



Acrolasia sqtialida Hook. f. in Transact. Linn. Soc. XX. (1851) 222; Walp. 

 Ann. I. 320. 



Mentzelia alhicaulis Torr. Mex. Bound. (1859) 67. p. p. {ex Wats.). 



Annua. C a u 1 i s erectiis vel (?) subscandens, in sicco brunneo-virescens vel flavescens 

 vel albescens, teres, + manifeste longitudinalitev striatus, pilis brevissimis vei-ticillatim glochi- 

 diatis dense obtectus aliis eadem forma sed triplo vel qnadruplo longioribus crassioribusque 

 et aliis antrorsum spinuligeris paiciiis intermixtis, nunc subglaber, superne vel a basi ramosus, 

 ramis erecto-patentibus vel patentibns, gemmis serialibus nullis. Folia alterna, laxa, ambitu 

 lanceolata vel ovato-lanceolata vel late ovata vel triangulari-ovata, infima usque ad 15 cm 

 longa, 8 cm lata, sequentia sensim minora, apice acuta vel breviter acuminata, regulariter vel 

 + irregulariter serrata vel serrato-dentata vel in media parte + profunde incisa usque semi- 

 triloba, lobis irregulariter serratis vel serrato-dentatis, basi cuneata vel + abrupte in petiolum 

 0,2 — 5 cm longiim angustata vel saepius subcordata usque cordata, supra pilis longis anti'orsum 

 spinuligeris + parce adspersa, aliis verticillatim glochidiatis rarissime intermixtis, subtus pube 

 canlis, scabra vel scaberrima. Flores in apice caulis ramorumque in cymas dispositi, cymis ad 

 sexies et ultra bifurcatis, numquam in monochasia abeuntibus, sessiles; prophylla eupbylloidea, 

 sensim decrescentia, petiolo brevi, vel saepius subsessilia. Calycis tubus teres cylindraceus, 

 inferne vel ad basin vix attenuatus, 0,6 — 1,1 cm longus, 2 — 3,5 mm erassus, pube caulis, sed 

 pilis antrorsum spinuligeris nullis vel subnullis, supra ovarium paululum vel vix productus; 

 lobi in aestivatione inferne quincuncialiter sibi imbricati, apice aperti, alabastrum ovato-oblongum 

 breviter acuminatum formantes, lanceolati vel lineari-lanceolati, longissime aeuminati, intus 

 brevissime ac teniiiter pilosi, extrinsecus pilis minimis verticillatim glochidiatis densissime ob- 

 tecti, aliis antrorsum spinuligeris parcius intermixtis, 3 — 4 mm longi, 1 — 1,5 mm lati, in fructu 

 persistentes erecti, non reflexi, emarcidi, viriduli. P e a 1 a 5, in aestivatione valde imbricata 

 obovata vel oblongo-obovata vel obovato-orbicularia, basi sensim angustata et cum staminibns 

 arcte in annulum connata, apice acuta, 4 — 8 mm longa, 2,5 — 4 mm lata, glaberrima vel dorso 

 hispidula. Squamae petaloideae nullae. Filamenta 20 — 30, 1 — 2-seriata, cum petalis in 

 annnlum connata 3 — 4 mm longa, omnia lineari-filiformia, aequalia, vel exteriora saepius sensim 

 i late petaloideo-dilatata, sed omnia fertilia. Antherae oblongae vel ovali-oblongae, apice 

 basique vix emarginatae, er. 0,8 mm longae, 0,5 — 0,6 mm latae, basi vel dorso paullo supra 

 basin affixae, lateraliter dehiscentes, defioratae non contortae. Discus glaber. Stylus ante 

 anthesin antheras superans, postremo 4 — 5 mm longus, filiformis, glaber angulatus, e lamellis 

 3 conflatus, apice sinistrorsum contortus, intus concavus, apice dense papillosus, in fructu per- 

 sistens, postremo cum calycis lobis emareidus ac caducus. Capsula cylindracea vel rarissime 

 subcylindracea, inferne non vel vix attenuata, teres, striis inconspicuis, sessilis, basi obtusa, 

 1,7 — 2,5 cm longa, 3—5 mm crassa, brnnneo-viridula, postremo brnnneo-nigrescens, scaberrima, 

 chartacea vel subchartacea, intra lobos calycinos 3-valvis, valvis triangulari-semiorbicularibus 

 incrassatis, cum placentis alternantibus; placentae 3 latissimae intervallis nitentibus glabris 

 duplo vel triplo latiores irregulariter plicatae rugosaeque ac manifeste prominentes. Semina 

 6 — 9, in placentis uniseriata, verticalia, pendula, funiculis nullis, irregulariter ovato-oblonga 

 vel oblonge -subrectangularia, griseo-Havescentia, 2,5 — 3,5 mm longa, 1,5 mm lata, medio er. 



