Classification of Plants 



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the Cactus plant, the stem may be reduced to a roundish or 

 club-shaped body, surrounded with cushions of leaf bases. 

 Frequently a pair of stout thorns represent stipules of abortive 

 leaves. An axillary thorn (reduced inflorescence) occur in 

 some species. {Cactus has clustered thorns.) What at first 



i 



Fig. 306. — Euphorbia Lathy ris, L. I, Fart of a plant. II. Inflorescence. 

 III. Male flower (magnified). (From Thom6 and Bennett's "Structural and 

 Physiological Botany".) 



seems to be a single flower is an inflorescence consisting of a 

 group of staminate flowers and a single pistillate flower. The 

 pistillate flower is raised on a stalk, and is reduced to an ovary. 

 Each staminate flower is also raised on a little stalk or pedicel, 

 and consists of a single stamen. The central stamens ripen 

 first. The whole inflorescence is surrounded by a cup-shaped 



