694 



EUPHORBIACEAE 



usually present, but often small or rudimentary, alternating \vith glands : stamens 5 or 

 more, inflexed in the bud. Pistillate flowers clustered or loosely racemose below the stam- 

 inate : sepals 5-10 : petals usually wanting : ovary mostly 3-celled : ovule one in each cav- 

 ity : styles or stigmas once, twice or many times 2-cleft. Capsule splitting into 2-4 (usually 

 3) 2-valved carpels. Seeds one in each carpel, smooth or minutely pitted. The plants 

 flower from spring to fall or throughout the year in many cases. 



Staminate and pistillate flowers with petals. 



Staminate flowers with petals, or both staminate and pistillate without petals. 

 Petals present in the staminate flowers, wanting or rudimentary in the pis- 

 tillate. 

 Plants with scaly foliage. 

 Plants with stellate-pubescent foliage. 



Pistillate calyx mostly not accrescent : leaf-blades entire. 

 Leaf-blades ovate to oblong or broadly lanceolate. 

 Leaves with ovate to narro\vly ovate blades. 

 Stamens 10. 

 Stamens more than 10. 



Styles 3, twice 2-parted or 4-parted. 

 Styles 3, 2-parted. 

 Leaves with oblong or broadly lanceolate blades. 

 Staminate raceme less than 5 cm. long. 

 Staminate raceme more than 5 cm. long. 

 Leaf-blades linear or narrowly oblong. 

 Blades narrowly linear, glabrate above. 

 Blades narrowly oblong, minutely stellate above. 

 Pistillate calyx mostly accrescent : leaf-blades toothed or entire. 

 Leaves with toothed blades. 

 Shrubs. 

 Herbaceous annuals. 



Sepals of pistillate flowers glabrous or nearly so. 

 Sepals of pistillate flowers pubescent. 

 Leaves with entire blades. 

 Plants annual. 



Pistillate flowers not pendulous from the base of the'.racemes. 

 Sepals 6-8, equal or nearly so : styles twice or more 2-cleft. 

 Lower leaves with lanceolate, oval or ovate blades : 

 sepals not hooded. 

 Petioles long, tomentum of inflorescence purplish. 

 Petioles short, tomentum of inflorescence yellowish. 

 Lower leaves with linear or linear-lanceolate blades : 

 sepals hooded. 

 .Sepals 5, very unequal : styles 2-cleft. 

 Pistillate flowers early droopiiigi from the base of the racemes. 

 Ovary 3-celled : capsules 3-seeded. 

 Ovary 2-celled : capsule 1-seeded. 

 Plants shrubby. 

 Petals wanting in both the staminate and pistillate flowers. 

 Plants perennial or shrubby. 



Staminate raceme short, 3 cm. or less. 

 Staminate raceme long, 3 cm. or more. 

 Plants annual. 



1. C. Alabamensis. 



2. C. argyranthemus. 



3. C.fruticnlosus. 



4. C. Berlandieri. 



5. C. suaveokns. 



6. C. Torreyanus. 



7. C. Cortesianus. 



8. C linearis. 



9. C. Firgusonii. 



10. C. betuUnuB. 



11. C. Floridanuf. 



12. C. glandulosus. 



13. C. capitatus. 



14. C. Engelmannii. 



15. C. ElUottii. 



16. C. leucophyllus. 



17. C. Lindluimerianus. 



18. C. monanthogynuf. 



19. C. corymbulosus. 



20. C. pundatus. 



21. C. Nco-ilexicanus. 

 '22. C. Texenm. 



1. Croton Alabamensis E. A. Smith. A much branched evergreen shrub 2-3 m. 

 tall, with a grayish white bark, the stem sometimes becoming 6 cm. thick. Leaf-blades 

 oblong to oblong-lanceolate, 5-8 cm. long, firm-membranous, green and glabrate above, 

 clothed beneath with silvery overlapping scales, usually without glands at the slightly 

 oblique base, short-petioled : racemes 3-5 cm. long : flowers sometimes numerous : stami- 

 nate 10-20 ; sepals and petals ciliate ; stamens 10-25 : pistillate flowers 4-7, their pedicels 

 becoming 4-8 mm. long ; sepals 3-4 mm. long ; petals scaly without ; glands 5 : capsules 

 3-lobed, 6-8 mm. long, depressed at the apex, scaly : seeds oval, biconvex, 5-7 mm. long. 



On limestone hills, middle Alabama. 



2. Croton argyrdnthemus Michx. A perennial shrubby plant 3-6 dm. tall, with 

 silvery or somewhat rusty foliage and approximate brandies. Leaf-blades various, the 

 lower ones obovate to oval, the upper oblong to oblong-lanceolate, 1-5 cm. long, blunt, 

 scaly or glabrate above, clotlied with silvery scales beneath, narrowed to petioles which are 

 :i-2 as long as the blades : racemes 2-5 cm. long : staminate flowers often 10-15 ; sepals 

 lanceolate, acute ; petals oblong, scaly without ; stamens mostly 10 ; filaments swollen at 

 the base : pistillate flowers few, often nearly sessile ; sepals 5-7, partially united, acute ; 

 petals Avanting ; glandular disk entire or 5-lobed : capsules 3-lobed, globular or oval- 

 globose, about 5 mm. long, depressed at the apex : seeds biconvex, less than 5 mm. long. 



In dry soil and pine lands, Georgia and Florida to Texas and New Mexico. 



3. Croton fruticulosus Engelm. A slender branched shrub 1-2 m. tall, with gray 

 or yellowish tomentum, tlie branches densely stellate-tomentose. Leaf-blades ovate to 

 narrowly ovate, 3-8 cm. long, acute or acuminate, entire or remotely glandular-denticulate. 



