546 



ARBORETUM ET FRUTICETUM BRITAXNICUM. 



Genus III. 



PJ'A L. The Iva. Lin Si/st. Syngenesia Necessaria. 



Identification. Lin. Gen. PI., 1429. ; Ait. Hort. Kew., ed. 2., vol. 5. p 181. 

 Derivation. Uncertain. Perhaps from Yua, a name used by the elder botanists. 



Gc7i. Char., S^c. Flowers moncecious, male and female on the same head: 

 female ones few on the same head, in a single series around the circum- 

 ference, they are tubular or campanulate ; the male flowers are numerous 

 in the disk, they are tubular and 5-toothed. Jnvolucrum usually 3 5- 

 leaved, campanulate. Scales ovate, in one series ; rarely imbricate, with 

 .3 or 4 series of scales. Receptacle fiat, beset with linear or linear spathu- 

 late palese. Styles on the female flowers subulate, exserted, rather hispid; 

 those of the males shorter, and thickened at top. Achenia of the disk 

 abortive, those of the ray a little compressed, naked, but furnished with 

 horns. (G. Don.) 



Leaves simple, opposite, exstipulate, deciduous ; lanceolate, serrated. 

 Flowers in terminal heads, solitary or three together, constituting a folia- 

 ceous terminal raceme. Suffrutescent deciduous shrubs, with the habit of 

 yJrtemisM, but readily distinguished by the moncEcious flowers. Indigenous 

 in Nortli America, on the banks of rivers. There is only one shrubby 

 species in British gardens. 



j 1. /. frute'scens Z. The shrubby Iva. 



Idenlificntiun. Lin. Amoen. Ac, 3. p. 25. ; Willd. Sp. PI., 3. p. 2387. ; Pursh 



Sept., 2. p. 580. 

 Synont/mes. yjgcrato aflfinis peruviana frutescens Pluk. Aim. 12. t. 27. f. 1. ; 



Bastard Jesuits' Bark Tree 

 Engravings. Pluk. Aim., 12. t. 27. f. 1.; and OMvfig. 1020. 



Spec. Char., Sfc. Leaves lanceolate, deeply serrated, rough 

 with dots. {Willd.) A sufiruticose deciduous bush, of 

 little or no beauty in the popular sense of that word. New 

 England to Florida, on the sea coast. Height 3 ft. to 4 ft. 

 Introduced in 17 II. Flowers greenish white; August 

 and September. 



In sheltered dry situations it is tolerably l^iardy ; but, when 

 freely exposed in moist soil, it is apt to be killed to the 

 ground in severe winters. Cuttings. The I\'a frutescens 

 can, however, hardly be considered a truly ligneous plant. 



1020. /. fn;tesceni. 



Genus IV. 



SANTOLPNA Tourn. The Santolina, or Lavexder Cotton, Lin. S^sl. 



Syngenesia -.'Equalis. j 



Identification. Tourn., t. 260. ; Lin. Gen. P!., 1273. ; Less. .S.ra. Gen. Compos., p. a9. ' 



Synonymcs. Santoline, Fr. ; Hciligenpflanze, Gcr. ; Santolina, Ital. 



Derivation. From sanctus, holy, and linum, flax ; so called from its supposed medical qualities. '- 



Gen. Char., ^-c. Heads many-flowered, sometimes homogamous, and somej 

 times heterogamous. Floivers of the ray few ; female, from abortion ; some- 

 what ligulate. Receptacle convex, subhemispherical, furnished with oblong 

 half-flower-clasping palere. Involucrum usually campanulate, with im 

 bricate adpressed scales. Tube of corolla usually produced at the basf. 



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