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EVO'LYULUS. (From evolvo, the oppo- 

 site to Convolvulus; referring to the 

 plants not twining. Nat. ord., Bindweeds 

 [Convolvulaceae]. Linn., b-Pentandria 2- 

 Digynia. Allied to Convolvulus.) 



For culture see CONVO'LVOLUS. All blue- 

 flowered trailers, except where otherwise specified. 



HARDY ANNUAL. 



E. Nuttallia'nus (Nuttall's). . July. N. Amer. 

 1824. 



STOYE EVERGREENS. 

 E. cxru'leus (sky-blue). July. Jamaica. 1845. 



lanceola'tus (spear-head-teauecO. June. S. 



Amer. 1818. 



latifo'lius (broad-leaved). 2. White. June. 



Brazil. 181Q. 



purpu'reo-cceru'lcus (purplish-blue). lj. July, 



Jamaica. 1845. 



irillo'sus (shaggy). 1. July. S. Amer. 1810. 



STOVE ANNUALS. 



E. alsinoi'des (chickweed-like). . July. E. Ind. 

 1817- 



emargina'tus (end-notched). 1. September. 



E. Ind. 18i6. 



Qange'ticus (Ganges). 1. July. E.Ind. 1820. 



Mrsu'tus (hairy). . July. Trinidad. 1818. 



inca'nus (hoary), $. July. S. Amer. 1810. 



linifo'lius (flax-leaved). 2. August. Jamaica. 



1/32. 



nummula'ris (moneywort-like), f . September. 



Jamaica. 18 16. 



seri'ceus (silky). & White. July. W. Ind. 1816. 



E'XACUM. (From ex, out of, ago, to 

 drive ; supposed virtue of expelling poison. 

 Nat. ord., Oenliauworts [ Gentian acese]. 

 Linn., 4c-Telrandria l-Monogynla. Allied 

 to Chironia.) 



Hardy annuals. Sow in April, in a moist bor- 

 der, in which there is a portion of peat. 

 E, maera'nthvm (large-flowered). l$. Purple. 

 December. Ceylon. 1853. 



pulcht'llum (pretty). . Pink. August. New 



Jersey. 1826. 



tetrago'num (four-angled). ! Blue. August. 



Nepaul. 1820. 



bi'culor (two-coloured). 1. Pale purple. 



June. Corcan. 1846. 



EXC^SCA'RIA. (From excaco, to Wind ; 

 the juice and smoke of burning branches 

 injure the eye-sight. Nat. ord., Spurge- 

 worts [Euphorbiacere]. Linn., 22-I}icccia 

 13-Polyandria. Allied to Gussonia and 

 Hippornane.) 



Stove evergreen shrubs, with white flowers ; 

 cuttings in sandy soil, under a bell-glass, in 

 spring or autumn ; fibry, sandy loam. Summer 

 temp., 60 to 75; winter, 4o to 55. 

 E. Agallo'cha (Ceylon). 5. May. E.Ind. 1820. 



glandulo'sa(glmded'). 5. May. Jamaica. 1821. 



serra'ta (s&w-leaved). 6. May. Chili. ]/96. 



EXCRESCENCE. Independently of Galls, 

 which are caused by the punctures of 

 insects, and the swellings which always 

 accompany Canker, the excrescences 

 which injure the gardener's crops are 



very few. That which appears above 

 the point of union between the scion and 

 stock is caused by the former being tbe 

 freer grower of the two, and is a warning 

 that should be remembered, for it cur- 

 tails the longevity of the tree, the supply 

 of sap gradually becoming inefficient. 

 The excrescences which occur upon the 

 branches of some apples, as those of the 

 codling and June-eating, cannot be looked 

 upon as disease, for they arise from con- 

 geries of abortive buds, which readily 

 protrude roots if buried in the soil, mak- 

 ing those among the few apples which 

 can be propagated by cuttings. Of a 

 similar nature are the huge excrescences 

 so prevalent on aged oaks and elms. Bul- 

 bous excrescences are formed upon the 

 roots of many plants if compelled to grow 

 upon a soil drier than that which best 

 suits them. This is the case especially 

 with two grasses, Phle'um prate'nse and 

 Alope'citnis genicula'tus, and is evidently 

 a wise provision of a nature to secure the 

 propagation of the species, for those 

 bulbs will vegetate long after the re- 

 mainder of the plant has been destroyed 

 by the excessive dryness of the soil. 



EXOGO'NIUM. (From exo, external, and 

 gonu, a joint; referring to the stems. Nat. 

 ord., Bindweeds [Convolvulaceffi]. Linn., 

 5-Penlandria \-Monogynia. Allied to 

 Ipomrea.) 



E. pu'rga is the true source of the best kind of 

 Jalap. A beautiful crimson-flowered, greenhouse 

 twiner, not a stove climber, as mentioned erro- 

 neously in books : we have even flowered it beau 

 tiftflly in the open air. Greenhouse evergreen 

 feffiners ; cuttings of short side-shoots in sandy- 

 soil, under a bell-glass, and in bottom-heat. Sum* 

 mer temp,, 55 to 75 ; winter, 45 to 50. 

 &.fitifo'rme (thread-shaped). 10. Purple. Oc- 

 tober. W. Ind. 1823. 



pu'rga (purgative. True Jalap). 10. Rose, 



purple. September. Vera Cruz. 1838. 



repa'ndum (wavy-edged). 10. Scarlet. June. 



W. Ind. 1793. 



EXOSTE'MMA. (From exo, externally, 

 and sttmma, a crown ; referring to the 

 flower-heads. Nat. ord., Cinchonads 

 [Cinchonacese]. Linn., 5-Pcntundria 1- 

 Monogynia. Allied to Luculia.) 



Stove evergreen tree. Cuttings of ripe young 

 shoots in sand, under a glass, in bottom-heat ; 

 loam and peat. Summer temp., 60 to 80 9 ; win- 

 ter, 50 to 55. 



E. tongiflo'rum (long-flowered). 30. White. 

 June. Caraccas. 1820. 



EXOTICS. Plants belonging to a country 

 different from that in which they are 

 growing. 



EXTRAVASATED SAP may arise from five 

 causes. 



