HORACE MANN ON HAWAIIAN PLANTS. 529 



XV. Notes on Alsinidendron, Platydcsma, and Brighamla, New Genera of Hawaiian Plants ; with an 

 Analysis of the Hawaiian Flora. By Horace Manx. 



Read December 2, 1868. 



O^E of the new genera described in the " Enumeration of Hawaiian Plants," published by 

 the late Mr. Horace Mann, and named in his honor, Hesperomannia, has been figured in 

 these Memoirs, Plate XX, and the three here presented were carefully examined by Mr. 

 Mann ; and from his notes, the following descriptions are mainly drawn. The Plates are 

 from drawings by Mr. W. T. Brigham. 



CARYOPHYLLACE^H. 



Alsinidendron H. Mann. Plate XXI. 



Calyx quadripartitus, sepalis decussatim imbricatis ovalibus subcarnosis albidis etiam 

 sub anthesi conniventibus, raro cum quinto minimo interne Petala et staminodia nulla. 

 Stamina decern, margini disci tenuissimae basi calycis accreti inserta: filamenta filiformia : 

 antherae lineari-oblongae, utrinque emarginatse. Ovarium uniloculare ; ovulis plurimis colu- 

 mellas centrali affixis: styli quatuor ad septem, breviter filiformes, apice intus stigmatosi. 

 Capsula quatuor ad septem-valvis, polysperma. Semina estrophiolata. Frutex Hawaiiensis, 

 orgyalis, fere glaber ; ramis foliosis ; foliis oppositis amplis ovatis ovalibusque cuspidato- 

 acuminatis basi in petiolum subito angustatis eximie trinervatis subeveniis ; cymis pluriflori- 

 bus pedunculatis ex axillis superioribus, floribus subglobosis in pedicellis filiformibus pendulis. 



Alsinidendron irinerve H. Mann. Proc. Bost. Soc. Nat. Hist., Vol. X, p. 312. 



Growing on the Kaala Mountains, Oahu, at an elevation of about two thousand feet, — a 

 glabrous branching shrub about six feet high. Leaves three or four inches long, and one and 

 a half to two inches wide, of a somewhat chartaceous texture, oval or ovate, cuspidate-acumi- 

 nate, tapering abruptly at the base into a margined petiole about an inch long, and with three 

 strong ribs running from the base to the very apex. Cymes from the axils of the upper 

 leaves, on peduncles an inch or more long. Flowers pendulous from the ends of long (3-8 

 lines) capillary pedicels, somewhat globose in shape, a little truncated at the base, and of a 

 light or whitish color. Sepals four (rarely with a minute internal fifth), about four lines 

 long, a little fleshy at the base, but with thinner margins and apex, closely imbricated, the 

 two outer completely enclosing the two inner in the bud. Petals and staminodia none, 

 stamens ten, — shorter than the calyx; the filaments arising from the margin of a thin 

 perigynous disk, and about as long as the oblong linear emarginate anthers, which are erect 

 and affixed by a deeply notched base. Ovary ovoid ; st3des short, four to seven. Capsule 

 membranaceous (only the immature seen), and probably not opening by valves. Seeds 

 numerous, borne on a central placenta, roughened by longitudinal lines of blunt tubercles. 

 (Mann and Brigham, Coll. 5S2. Also Hillebrand, fide Oliver in lift.) 



RUTACiE. 

 Platydesma H Mann. Plate XXII. 

 Flores hermaphroditi. Calyx quadrisepalus. persistens, valde imbricatus ; sepalis rotundis, 

 exterioribus majoribus interiora ajstivatione includentibus. Petala quatuor, Eestivatione late 



MEMOIRS nilST. SOC. SAT. hist. Vol. I, Pt 4. 133 



