DICTYOSPERMA 



DIDYMOSPERMA 



1005 



darker green, the primary veins and margins dark 

 red, the redness disappearing very much in adult 

 plants: branches of the spadix longer and more reflexed. 

 Young plants of this may be used for table decora- 

 tions as the plant grows quickly and is attractive in 

 juvenile condition. JARED G. SMITH. 



N. TAYLOR, f 



DICYRTA (twice curved, referring to structure of 

 fls.). Gesneridccse. Very closely related to Achimenes 

 with which some authors unite it, differing in the 

 smaller fls., and diverging anther-cells. Low-growing 

 slender villous herbs with creeping roots: lys. opposite, 

 membranaceous: fls. axillary, small, white or pale 

 lilac, sometimes spotted; corolla-tube declinate, the 

 limb oblique with 5 nearly equal spreading lobes; 

 stamens affixed in the base of the corolla-tube, included, 

 the anther-cells distinct. Two species occur in Guate- 

 mala. D. Candida, Hanst. & Klotzsch (Achimenes 

 Candida, Lindl. Diastema grdcile, Regel). To 1^ ft.: 

 Ivs. ovate to ovate-lanceolate, acuminate, serrate, 

 short-petioled : fl. on a bracted pedicel that much 

 exceeds the petiole, white, tubular-campanulate, the 

 lowest lobe projecting. Summer. The other species is 

 D. Warscewiczidna, Regel (A. misera, Lindl.), appar- 

 ently not in cult.: fls. smaller. L H. B. 



DIDfSCUS: Trachymene. 



DIDYMOCARPUS (twin fruit). Gesneridcese. Attrac- 

 tive warmhouse herbs, with few showy flowers. 



A polymorphous genus, distributed in E. India, 

 Malaya, China, and Trop. Afr., differently named and 

 defined by different authors. Roettlera is an older 

 name, and has been used recently, but it is discarded by 

 the "nomina conservanda" list of the Vienna code. 

 The genus includes Chirita and Trachystigma accord- 

 ing to Fritsch, and it then numbers more than 100 

 species. Bentham & Hooker omit Chirita, which differs 

 in its 2-parted stigma, always 2 stamens, and other 

 characters; in this work it is kept distinct. Didymo- 

 carpus comprises plants that are caulescent or nearly 

 acaulescent, sometimes woody, of various habit: Ivs. 

 radical and cauline, those on the st. opposite or alter- 

 nate, crenate, more or less wrinkled and hairy: fls. 

 violet, blue, white or even yellow, on few-fld. scapes 

 or axillary peduncles; corolla with an elongated tube 

 which is widened at the throat or ventricose, the limb 

 spreading and somewhat 2-lobed ; stamens 2 or rarely 4, 

 the anthers connivent or coherent and cells divergent; 

 style long or short, the stigma little dilated and entire 

 or nearly so. The species require the treatment given 

 the warmhouse gesneriaceous plants; usually difficult 

 to grow, or are soon lost because seeds may not be pro- 

 duced. Several species are mentioned in horticultural 

 literature; but the following are more recently intro. 

 and are likely to be cult, or perhaps in the trade. They 

 are low herbs with few Ivs., resembling Streptocarpus. 

 Many new species have recently been added to this 

 interesting genus, and a number of them may be 

 expected to appear in cult. 



cyaneus, Ridley. Stemless: Ivs. in a rosette, ovate, 

 elliptic or obovate, ascending, somewhat obtuse, to 6 

 in. long, crenate-serrate, soft pubescent, petioled: fls^ 

 deep blue, trumpet-shaped, about 1J^ in. long, with 

 rounded spreading lobes, 4 or 5 on a scape. Malaya. 

 B.M. 8204. Blooms in autumn; should have warm 

 treatment, such as is given Streptocarpus. 



Veitchiana, W. W. Smith. Eight in. or less: Ivs. 2-4 

 pairs, ovate, somewhat cordate at base, serrate, 4 in. 

 or less long, stalked: fls. lilac with longitudinal lines, 

 tubular, nearly 1% in. long, in few-fld. axillary cymes. 

 China. L. H. B. 



DIDYMOCHL.<ENA (Greek, twin cloak; alluding to 

 the indusium). Polypodiacese. Greenhouse ferns of 

 rather coarse foliage. 



Indusium elliptical, emarginate at the base, attached 

 along a central vein, free all around the margin. One or 

 2 species. Large coarse ferns somewhat resembling the 

 shield ferns, Dryopteris, in habit and gross appearance. 



D. lunulata is a very distinct fern. It looks hke a tree 

 maidenhair, but the stems are thick and fleshy and the 

 leaves are fleshier than any Adiantum. In cultivation 

 the trunk is only a few inches high, but the fronds are 

 4 to 6 feet long and densely covered with long, brown, 

 chaffy scales and has a metallic luster. This is a warm- 

 house fern, and may be used for subtropical bedding. 

 It has a bad trick of dropping its pinnules if allowed to 

 get too dry at the root, but soon rallies under liberal 

 treatment. 



lunulata, Desv. (D. trunculdta, Hort.). Fig. 1260. 

 Lvs. clustered from an erect rigid st., bipjnnate, 3-6 

 ft. long; pinnules almost 

 quadrangular, %-l in. 

 broad, entire or slightly 

 sinuate, each bearing 2-6 

 sori. Cuba to Brazil; the 

 same or an allied species in 

 Madagascar and Malaya. 

 D. lunulata is a very 

 attractive fern while in a 

 small state, but its decidu- 

 ous articulated pinnules 

 are a drawback as a com- 

 mercial species, rendering 

 it of little value for house 

 decoration. 



L. M. UNDERWOOD and 



W. H. TAPLIN. 



DIDYMOPLEXIS 



(double or twin plaits). 

 Orchiddcese. One sapro- 

 phytic orchid with leafless 

 sts. D. pdllens, Griff., 

 has been cult, abroad but 

 is probably not in the 

 trade: root branch- 

 ing and tuberous, 

 bearing a st. 4-6 in. 

 high with loose 

 sheaths : racemes 

 terminal, with 4-8 

 small brownish' or dull 

 yellow-white fls.; perianth 

 J^in. diam.; lip stipitate, 

 transversely oblong, with 

 3 nerves and a papillose 

 disk; pedicels becoming 

 greatly elongated after fer- 

 tilization. E. India. The 

 genus Didymoplexis comprises 2 or 3 species (Leucor- 

 chis is a more recent name), in India, Malaya and the 

 Pacific Isls., characterized by simple flexuous scapes, 

 dorsal sepals and petals connate into a 3-parted upper 

 Up, the lateral connate into an entire or 2-parted lower 

 lip, the regular lip inserted on the foot of the column, 

 very short and broad, entire: caps, becoming very long- 

 pedicelled. Apparently of little horticultural interest. 



DIDYMOSPERMA (Greek, double-seeded). Pal- 

 macese, tribe Arecese. Low or almost stemless pinnate 

 oriental palms. 



Leaves terminal, unequally pinnatisect, silvery- 

 scaly below; segms. opposite, alternate, solitary, or 

 the lower ones in groups, cuneate at the base, obovate- 

 oblong or oblanceolate, sinuate-lobed and erose. the 

 terminal one cuneate; margins recurved at the base; 

 midnerve distinct, nerves flabellate; sheath short, 

 fibrous: spadices with a short, thick peduncle and thick 

 branches; spathes numerous, sheathing the spadix; 

 fls. rather large; calyx 3-lvd., corolla with 3 stiff petals; 



1260. Didymochlana lunulata. 

 (XM) 



