128 ASCLEPIADEZ. XXIII. Hoya. 
short, subulate, erect, inner angles. h. ^. S. Native of the 
East Indies, at Korma, Hamilton, and at Segaen, Wall. Ham. 
herb. no. 770. Wall. ascl. no. 24, f. 146, and 156, without a 
name. Lakun of the Hindoos. 
Lakun Hoya. Shrub tw. 
T + Species described by Vahl, under the generic name of 
Sperlingia, which name ought to take precedence of Hoya, being 
the oldest, which we have still retained, on account of that 
name being generally received. Both species are probably 
identical mith two of those described above. 
36 H. vrgnrICILLA'TA ; climbing, rooting; stems terete, gla- 
brous; leaves 4 in a whorl, petiolate, oblong, acuminated, acute, 
fleshy, glabrous, veinless; umbels pedunculate, copious; pedi- 
cels compressed, filiform ; segments of corolla triangular, acute 
at both ends, retusely sub-bicornute outside, on the outer margin : 
with inflexed, conduplicate edges ; corona a simple star, covering 
the genitals, having the lobes equal in length to the segments 
of the corolla, complicate, lanceolate, with an elevated line in 
the middle, and a corresponding furrow on the opposite side, 
yellowish, shining; follicles 6-8 inches long, glabrous. h. ^. 
S. Native of the East Indies. Sperlíngia verticillàta, Vahl, in 
act. soc. hist. nat. hafn. 6. p. 113. 
Whorled-leaved Hoya. Shrub twining. 
37 H. orPosirA; leaves opposite. h.%.S. Native of the 
East Indies. Sperlíngia opposita, Vahl, 1. c. p. 114. Nummu- 
laria láctea major, Rumph. amb. 5. p. 470. t. 175. f. 1. Very 
like H. verticillàta ; but differs, in the opposite leaves, the nar- 
rower petioles, which are convex beneath, and concave above; 
while, in that species, they are flattened and depressed, almost an 
inch long, succulent, and articulated at the base. 
Opposite-leaved Hoya. Shrub twining. 
Cult. The species of Hoya all bear handsome waxy blossoms, 
disposed in simple umbels. They grow freely in a mixture of 
loam, peat, and sand, and are otherwise easily managed. They 
are readily propagated by cuttings, in a moist heat. 
XXIV. PTEROSTELMA (from «repov, pteron, a wing; 
and sreAua, stelma, a crown; leaflets of corona membranous.) 
Wight, contrib. ind. bot. p. 39. 
Lin. syst.  Pentándria, Digynia. Corolla rotate, 5-cleft. 
Stamineous corona 5-leaved; leaflets membranous, with re- 
flexed sides: having the inner angles drawn out into subulate, 
erect teeth. Anthers terminated by a membrane ; pollen masses 
erect, fixed by the base to the back of the corpuscles. Stigma 
apiculated.—A twining? or decumbent shrub. Leaves oppo- 
site, oblong, acuminated, fleshy. Flowers rather large. Co- 
rolla deeply 5-cleft; with linear-lanceolate segments, and a 
pilose tube. Margins of the leaflets of the corona conniving, 
as the wings of butterflies are when sitting. This genus is 
nearly allied to Hòya, both in habit, and in the structure of the 
flowers, differing principally, in having foliaceous instead of 
fleshy leaflets of corona, and in the dorsal not lateral attachment 
of the pollen masses. 
1 P. acuminata (Wight, lc.) $.^. S. Native of Silhet. 
—Wall. ascl. no. 129, without a name. 
Acuminated-leaved Pterostelma. Shrub? 
Cult. See Hoya, above, for culture and propagation. 
XXV. PHYSOSTELMA (from $vca, physa, a bladder ; and . 
crepa, stelma, a crown; leaflets of corona inflated.) Wight, 
contrib. ind. bot. p. 39. 
Lin. syst.  Pentándria, Dyginia. Corolla rotate, spreading, 
repandly, 5-toothed. Stamineous corona 5-leaved ; leaflets in- 
flated, opposite the anthers. Anthers terminated by a mem- 
brane. Filaments bipartite from the base to the apex, each 
alternate part bearing an anther, close together, alternating with 
XXIV. PrEROSTELMA. 
XXV. Puysosterma. XXVI. Tyrornona. 
the leaflets of the corona. Pollen masses fixed by the base, 
erect, nearly cylindrical. Stigma depressed.—A twining shrub. 
Leaves opposite, ovate-lanceolate, acuminated, glabrous, fleshy. 
Umbels lateral, on longish peduncles, few-flowered. Flowers 
large. This curious genus is allied to Hoya in habit; but is at 
once distinguished from it, and every other, by the remarkable 
division of the filaments ; there being 10 filaments and 5 anthers. 
1 P. Warrícnuu (Wight, contrib. ind. bot. p. 40.) kh. S. 
Native of Singapore. Wall. ascl. no. 130, without a name. 
Wallich’s Physostelma. Shrub tw. 
Cult. For culture and propagation see Hoya, above. 
XXVI. TYLO'PHORA (rvXoc, tylos, a swelling, and 
popew, phoreo, bear; in reference to the ventricose pollen masses). 
R. Br. in mem. wern. soc. 1. p. 28. prod. p. 460.— Hoya species, 
Spreng. syst. 1. p. 843. 
Lin. syst.  Pentándria, Digynia. Corolla rotate, 5-parted. 
Stamineous corona 5-leaved ; leaflets simple, fleshy : having the 
inner angles simple and toothless. Anthers terminated by a 
membrane ; pollen masses erect, fixed by the base, with simple 
margins, transverse or ascending, minute, ventricose. Stigma 
mutic. Follicles smooth, attenuated at the apex, compressed, 
rather angular on one side. Seeds comose.—Twining herbs or 
subshrubs. Leaves opposite, membranous, flat. Umbels inter- 
petiolar, or disposed alternately along a common peduncle. 
Flowers usually small. 
The extreme minuteness of the pollen masses renders it diffi- 
cult to determine the situation this genus ought to occupy in 
the order. The form of the gynostegium and the leaves of the 
corona readily distinguish it from every other genus except 
Iphisia, but which differs in the pendulous pollen masses. As 
now defined, this genus is quite distinct from Hòya, to which 
Mr. R. Brown considered it so closely allied. Arnott. and 
Wight, contrib. ind. bot. p. 50. 
§ 1. Leaflets of stamineous corona depressed, fleshy, toothless 
inside, shorter than the gynostegium.—Species natives of New 
Holland. 
1 T. cranpirxora (R. Br. prod. p. 460.) umbels nearly ses- 
sile, simple, few-flowered; pedicels glabrous ; leaves cordate- 
ovate, acute, and are, as well as the branches, downy. b.^. S. 
Native of New South Wales, about Port Jackson. Hoya gran- 
diflóra, Spreng. syst. 1. p. 843. 
Great-flowered Tylophora. Fl. Ju. Jul. Clt. 1822. Sh. tw. 
2 T. BAnBA' TA (R. Br. l. c.) umbels usually twin; common 
peduncles shorter than the leaves ; corolla bearded ; leaves ovate, 
acute, quite glabrous. 1. ^. S. Native of New South Wales, 
about Port Jackson, Hoya barbàta, Spreng. syst. 1. p. 843. 
Bearded Tylophora. Fl. June, Jul. Clit. 1822. Shrub tw. 
3 T. riexvdsa (R. Br. l. c.) umbels alternate, sessile; com- 
mon peduncles flexuous ; leaves cordate-oblong, veiny ; corolla 
beardless. h. ^. F. Native of New Holland, within the 
tropic. Hoya flexuósa, Spreng. syst. 1. p. 843. 
Flexuous Tylophora. Shrub tw. 
4 T. vetutina ; stem twining; leaves cordate-ovate, acu- 
minated, tomentose ; flowers cymose; throat of corolla naked. 
h. ^. S. Native of New Holland.  Pergulària velutina, 
Spreng. syst. 1. p. 844. 
Velvety Tylopbora. Shrub tw. 
5 T. PANIcULA' rA (R. Br. l. c.) panicles dichotomous ; seg- 
ments of corolla ligulate above: leaves ovate, acuminated, 
smoothish: lower ones subcordate. h.™.S. Native of New. 
South Wales, about Port Jackson. Hoya paniculata, Spreng. 
syst. 843. 
Panicled-flowered Tylophora. Shrub tw. 
§ 2. Leaflets of stamineous corona very blunt, or bluntly 
