326 ARISTOLOCHIE.E. [AIIISTOI.OCIIIA. 



yellow ; tube slender, globose at the base, curved ; lip j in., oblong or ovate ; 

 throat dilated. Capsule %-\ in., pyriform, obtuse; peduncle decurvcd. 

 Seeds suborbicular, much compressed, granulate, deeply excavated on tho 

 ventral face. DISTRIB. Europe from Denmark southwards, W. Asia. 



ORDER LXVIII. EUPHORBIA'CEJE. 



Herbs, shrubs, or trees, juice often milky. Leaves usually alternate, 

 simple, often stipulate. Flowers small or minute, usually 1 -sexual, brae- 

 teate or involucrate. Calyx 0, or sepals 2 or more. Petals (in British 

 genera). MALE. Stamens 1 or more ; anthers didymous. Ov<n-y rudi- 

 mentary or 0. FEMALE. Ovary 2-3-lobed, 2-3-celled; styl-- 

 stigmas entire or lobed. Ovules 1-2, collateral, pendulous from the top ol' 

 each cell, funicle dilated over the micropyle. Capsule 2-3-lobed an I 

 -celled, cells 1-2 seeded. Seeds pendulous, testa usually enistaeeous, 

 funicle often swollen at the top (seeds carunculate), albumen copious 

 fleshy; embryo axile, radicle superior. DISTRIB. All climates except 

 Arctic; genera 180; species about 3,000. AFFINITIES. Close with .!/< 

 and Urticecc. PROPERTIES. Usually acrid, but too numerous to specify. 

 The above diagnosis includes the British genera of this vast Order, to emi- 

 merate all the characters of which would exceed the limits of this Flora. 



SUB-ORDER I. Euphor'biese. Ovules 1-2 in each cell ; raphe ventral. ( '/<- 



side, septicidal ; valves elastically breaking away from the seed- bearing ;;\ s. 



TRIBE I. EUPHOR'BIJE. Herbs or shrubs ; juice milky, titameng many, 



collected into a calyx-like involucre (perianth of some). Pistil solitary, 



pedicelled, 3-lobed, 3-celled 1. Euphorbia. 



TRIBI: II. ACAL'YPHE-ffi. Herbs or shrubs, juice not milky. Fl<,,i. ,.< 

 not in calyx-like involucres ; male with 3 valvate sepals ; feina'u a. 



2-3-celled ovary 2. Mercurialis. 



SUB-ORDER II. Buxe'oe. Ovules 2 in each cell ; raphe dorsal. G'/""/*' 

 loculicidal 3. Jbuxus. 



1. EUPHOR'BIA, L. Sn i:ci 



Herbs (the British species). Inflorescence of many male and one female 

 flower in a 4-5-lobed involucre (perianth of some); lobes with thick {.'lands 

 at the sinuses. MALE 11. a pedicelled stamen ; anther didymous. FI:M A i.i. 

 fl. Ovary on a lengthening pedicel, inclined or pendulous ; stigmas 2-iid. 

 Capsule 3-lobed, 3-valved, valves with a coriaceous exocarp sep;iral>i<: 

 from a hard 2-valved endocarp. DISTKIB. Of the Order; species 700. 

 KTYM. The old Greek name. 



SECTION 1. Leaves exstipulate. Branches (or stem, if simple) ter- 

 minated by umbels of forked branchlets (rays) subtended by a whorl of 

 leaves ; rays 2-bracteate at the forks. 



* Leaves alternate. Umbels 5- rarely 3-4- rayed. Glands of involucre 



transversely oblong reniform or orbicular, not cuspidate. 

 1. E. Heliosco'pia, L. ; annual, glabrous, rarely pilose, leaves obovato 

 serrate above the middle, upper bracts broadly ovate-cordate, capsule 

 smooth, seeds deeply pitted. Sun Spurge. 



