108 NATURAL HISTORY OF PLANTS. 



cactiform, perennial or annual, frequently with milky juice, lias 

 been divided into a certain number of sections,^ principally based on 

 tbe exterior character of the seeds, of the glands alternating with the 

 sepals, and upon the vegetative organs. The leaves, sometimes (espe- 

 cially in the species with thick stems) reduced to small tongues, are 

 either alternate or opposite and unsymmetrical exstipulate, or with 

 lateral stipules, membranous or glandular. The flowers, often 

 preceded by coloured bracts, are disposed in more or less compound 

 cymes, bi- or pluriparous, often uniparous, principally at the summit 

 of the inflorescence, this being axillary, or more usually terminal, 

 and frequently united ia a umbelliform mass. 



In some African species of Euphorbia^ the glands alternate to the 

 sepals, instead of being independent, are more or less widely united 

 in a lobed ring : the genus Synadenium^ has been made of them, 

 but we have only considered them as a section of Euphorbia. 



Beside Euphorbia is placed Pedilanthes, representing the irregular 

 form of it. The gynseceum and androceum remaia the same, the 

 calyx becomes extremely irregular, usually calceolate, generally as 

 if bilabiate, with a posterior lip represented by the posterior division 

 of the perianth, in itself bi- or tridentate, and an anterior lip formed 

 pf five sepals, larger and imbricated. "Within the posterior lip is 

 found a platform or furrow bearing one or a larger number of 

 sessile glands. The species of Pedilanthes are American. Their 

 vegetative organs are fleshy ; their leaves alternate, and their flowers 

 disposed in terminal or axillary cymes. 



According to another opinion, that which we have just considered 

 as the calyx* in Euphorbia and Pedilanthes, represents a multifloral 



cit. 7-188, 1262-1269, — H. Bn. in. Adansonia, canthium (Boiss.) — Sterigmanthe Kl. et Grcke. 



i. 58, 104, 139, 291 ; ii. 211 ; iii. 139 ; iv. 257 ; loc. cit. lOOf; 20. Euphorbium (Boiss.— -Doc*^- 



vi. 282 ; vii. 159, 375 ; ji.. 197. Imthes, Medmta, Tieisia, Haw. ; — Aiithacantha 



1 M. BoissiER (Prodr. 8) twenty 'seven of them Lem. in III. Mart. [1835], 69) ; 21. Ehisanthium 



are admitted ; 1. Anisophyllum (Haw. Syn. 159) ; (Boiss.) ; 22. Tiruenlli (Bois.*!.) ; 23. Lyciopsis 



2. Zygophytlidittm (Boiss.) ; 3. Cyttaroitpermum (Boiss.) ; 24. Fsmdaealypha (Boiss.) ; 25. Mu- 



(Boiss.); 4. Dichiliiim (Boiss.); 5. Alectoroctc- plibrbiastrtim (Kl. et GtUCKt:. loc. cit. 101); 26. 



nitm (ScHLTL. in Ziimtea, xix. 252) ; 6. Petaloma Tithymalus (Boiss.) — Scop, (nee Haw.) ; — Qal- 



(Rkvis.Atl. Joii.rn.ni);'!. Crossadenialfioi&s.) arrhaus Hakv. Syn. 143); — Emla Harv. 



8. Stachydium (Boiss.) ; 9. Tithymalopsis (Kl. Syn. 153) ; 27. Calycopeplus (Pi.), we have 



et. GrRCKE. he. cit. 33) ; 10. Trieherostigma (Kl. eeperated this last genus from JEuphorbia, 



et GuOKE. loc. cit. 41); 11. Portulacantrum and we join as sections Synadenium (Boiss.) 



(Boiss.); 12. C/ieirolepidium (Boisa.) ; IS. JSrc- Dccadenia (S.. Bs. in Jdaiisonia, US; — Cleopatra 



mophytum (Boiss.); 14. Kummidariopsia (Boiss.) Panch.), heeides Bongium (Boiss. Prodr. 



15. Poitisettia {Gr&s. in Hdini.Neu) Phit.Journ^ 1264, s.ISa.). 

 (1836) ; (Kl. et Grcke. loc. cit. 101) ; 16. s Boiss. Prodr. 187, 1269. 



Arlhrothammis (Kl. et Grcke. loc. cit. 62 ^ In Adansonia, va. 142. 



part.) ; 17. Catilanthium (Boiss.) ; 18. Gonoi- * Following the example of Touenefort. 



stoMB (H. Bn, iuAdansoniai i. 114); 19. Dia- 



