48 



ALNUS 



ALOCASIA 



S. Eu. Var. imperialis, Desf . Fig. 66. Lvs. deeply pin- 

 nately lobed with lanceolate or nearly linear lobes. Var. 

 incisa, Willd.(var. oxy acanthi fdlia, Spach.). Lvs. small, 

 deeply incised, like those of Cratcegus oxyacantha. Var. 

 laciniata, Willd. Lvs. pinnately lobed ; lobes oblong. 



66. Alnus glutinosa, var. imperialis (X 



Var. rubrin6rvia, Dipp. Lvs. large and shining, with red 

 nerves and petioles ; pyramidal tree of vigorous growth, 

 very handsome. 



A. acumindta, HBK. Tree: Ivs. usually ovate and pubescent 

 beneath, doubly serrate. C. Amer., north to Ariz. A. Alnobet- 

 ula, Hort.=A. viridis. -A. barbdta, G. A. Mey. Allied to A. 

 glutinosa. Lvs. pubescent on the veins beneath, ovate. Cauca- 

 .sus. Perhaps hybrid of A. glutinosaXsubcordata. A. Cana- 

 densis, Hort.=A. rugosa. A. communis, Desf.=A. glutinosa. 

 A.cordifblia, Teu.=A. cordata. A. crispa, Pursh= A. viridis. 

 A. firma, Hort.=A. Japonica or A. subcordata. A. glauca, 

 Michx.=A.incana. A.JorwMeraswj, HBK. Allied to A. acumi- 

 nata : Ivs. oblong-lanceolate, coarsely dentate. C. Amer. A. 

 macrocdrpa, Lodd., not Regel.=A. glutinosa var. A. macro- 

 .phylla, Hort.=A. subcordata. A. oblongdta, Willd.=A. gluti- 

 nosa, var. denticulata. A. oblongdta, Regel.=A. maritima. A. 

 oblongifdlia, Torr. Tree, 20-30 ft.: Ivs. oblong-ovate, cuneate, 

 doubly serrate, 2-3 in. long: strobiles X-l in. long, peduncled. 

 N. Mex. and Ariz. S.S. 9: 457. A. Oregana, Nutt.=A. rubra. 

 A. orientalis, Decaisne=A. subcordata. A. pubescens, Tsch. (A. 

 .glutinosaXincana) . Lvs. roundish-ovate or obovate, irregularly 

 serrate, pubescent beneath. Natural hybrid. A. rhombifblia, 

 Nutt. Tree, 60-80 ft.: Ivs. cuneate, oval or ovate, 2-3%in. long, 

 finely serrate, yellowish green and puberulous beneath : stro- 

 biles oblong, peduncled. W. N. Amer. S.S. 9: 456. A. serruldta, 

 Willd.=A. rugosa. A. Sibirica, Hort., not Fisch.=A. viridis 

 Sibirica. A.sinuata, Rydb. Allied to A. viridis. Shrub, 3-16 

 ft.: Ivs. slightly lobed, serrulate, glabrous, thin. W. N.Amer. 

 A. subcordata, C. A. Mey. (A. orientalis, Decaisne. A. firma, 

 Hort., not, S.&Z. A. macrophylla, Hort.). Tree, 30-50 ft.: Ivs. 

 rounded at the base, ovate or oblong, 2-6 in. long, crenately ser- 

 rate, often pubescent beneath. Allied to A. cordata. Caucasus, 

 Asia Minor. A. subrotunda, Hort.=A. glutinosa var. denticu- 

 lata. A. tenuifblia, Nutt. (A. incana, var. virescens, Wats. A. 

 occidentalis, Dipp.). Small tree, occasionally 30 ft.: Ivs. ovate, 

 2-4 in. long, slightly lobed and doubly serrate, green and nearly 

 .glabrous beneath. W. N. Amer. S.S. 9: 455. A. unduldta, 

 Willd.=A. viridis. 



ALFRED REHDER. 



ALOCASIA (name made from Colocasia). Aroidece. 

 Stove foliage plants, of 30 or more original species, 

 from trop. Asia and the Malayan Isls. Closely allied to 

 Caladium and particularly to Colocasia, which see. 

 These three genera differ chiefly in characters of fruit. 

 Monogr. by Engler in DeCandolle's Monographic Pha- 

 xnerogamarum, Vol. 2. In 1890, 52 species and specific- 



ally named hybrids were in cult. (Bergman, Jour. Soc. 

 Nat. Hort. France. I.H. 37: 80). 



Alocasias are propagated by suckers or cuttings of 

 the rhizomes, placed in small pots containing a mixture 

 of light, fibrous peat and sand in equal proportions, and 

 plunged in a close frame or propagating box with bot- 

 tom heat. They may also be grown from seeds sown in 

 4-inch pots, in a light, peaty soil in a temperature of 

 75 F. The month of March is the best time for propa- 

 gating. The evergreen species (as A. cuprea, longiloba, 

 Lowii, Hegina) thrive best in a compost of two parts 

 fibrous peat and sphagnum moss and one part lumps of 

 fibrous loam, to which should be added a sprinkling of 

 silver sand and a few nodules of charcoal to keep the 

 whole sweet. The herbaceous species (as A . macrorh iza ) 

 do best in good fibrous loam to which % of well-rotted 

 cow-manure or pulverized sheep-manure has been added. 

 Perfect drainage of the pots is absolutely necessary, 

 and in potting, the evergreen species should be coned 

 up two or three inches above the rim of the pot, and 

 finished off with a surfacing of live sphagnum moss. 

 The season of active growth commences about the first 

 of March, when they should be given a temperature of 

 70 at night, with a rise of 15 by day, and the atmos- 

 phere must be kept in a humid condition. They should 

 be given a position free from draughts and direct sun- 

 light. They require an abundance of water at the roots 

 as the leaves develop, and are greatly benefited by an 

 occasional watering of clear liquid sheep or cow-manure 

 water. To obtain the best development of the leaves, 

 heavy syringing should be avoided, but frequent spray- 

 ing on all fine days with an atomizer sprayer is very 

 beneficial. Towards winter the humidity of the atmos- 

 phere and the supply of water to the roots should be 

 reduced with the evergreen species, and gradually with- 

 held altogether as the leaves mature with the herba- 

 ceous species. The temperature during winter should 

 not fall below 60. Cult< by E- j. CANNING. 



The propagation of most of the Alocasias consists of 

 cutting up the stems, so that each piece will have at 

 least one dormant bud. The pieces should be placed 

 amongst moss, in a hot propagating frame, where they 

 vegetate quickly. Such kinds as A. Sanderiana, A. 

 macrorhiza,var.variegata,&nd A. Jenningsii (Colocasia) 

 have creeping rhizomes, at the ends of which small 

 resting tubers are formed. These should be carefully 

 collected, and the two first named started in a propa- 

 gating frame in a pan of moss and sand. A. Jenningsii 

 roots readily in ordinary soil. Most of the kinds require 

 a soil which is very fibrous, with a little moss added. The 

 pots should be half filled with potsherds as drainage. 

 Cult, by G. W. OLIVER. 



A. Lvs. distinctly notched or undulate on the margin. 

 princeps, Nicholson. Lvs. sagittate, the basal lobes 



narrow and spreading, the margins deep-sinuate; upper 

 surface olive-green, with darker veins, the under lighter 

 colored, with brown veins and margin; petioles brown- 

 spotted, slender. E. Ind. 



Sanderiana, Bull. Fig. 67. Lvs. long-sagittate, with 

 deeply notched margin, the basal lobes wide-spreading; 

 deep glossy green with metallic reflection, with promi- 

 nent white margins and veins; petioles brownish and 

 striped. Philippines. Gng. 1897: 84.- One of the best of 

 recent introductions. Runs into various forms, and has 

 entered largely into cultivated hybrids. 



AA. Lvs. plane and entire on the margin. 



B. Markings chiefly on the petioles, the blades green. 

 zebrina, Koch & Veitch. Lvs. triangular-sagittate ; 



petioles beautifully marked with large zigzag bands of 

 green. Philippines. F.S. 15:1541-2. 



Villeneiivei, Lind. & Rod. Lvs. sagittate-ovate, the 

 veins of lighter green and prominent, basal lobes very 

 unequal; petioles spotted with chocolate-brown. Large. 

 Borneo. I.H.34:21.-Namedfor de Villeneuve, Brazilian 

 ambassador to Belgium. 



BB. Markings or coloration chiefly on the leaf-blades. 



c. Veins and midrib light yellow. 

 Lindeni, Rod. Lvs. cordate -ovate, long-pointed, 8-12 

 in. long, bright green, with yellowish veins curving off 



