FIELDBOOK OF ILLINOIS WILD FLOWERS 



KEY TO FAMILIES — CONt'd 



17. Leaves compound; flowers large. . .BIGNONIA FAMILY p. 314 

 Leaves simple 18 



18. Leaves palmately veined MOONSEED FAMILY p. 114 



Leaves pinnately veined. .STAFF TREE FAMILY in part p. 187 



19. Leaves curiously shaped to hold liquids 



.PITCHER PLANT FAMILY p. 137 



Leaves reduced to prickles; stems fleshy and jointed 



CACTUS FAMILY p. 204 



Leaves scalelike; plants without ^reen color 



HEATH FAMILY in part p. 227 



Leaves of normal appearance 20 



20. Plants with milky sap 21 



Not thus 22 



1 1 . Corolla lobes completely reflexed . .MILKWEED FAMILY p. 242 

 Not thus DOGBANE FAMILY p. 238 



22. Leaves usually entire, elongate and parallel veined 76 



Leaves netted veined 23 



23. Corolla present 24 



Corolla lacking 25 



24. Petals separate 32 



Petals more or less united 53 



25. Stipules forming a sheath at each node 



BUCKWHEAT FAMILY p. 78 



Not thus 26 



26. Flowers perfect, borne in spikes PEPPER FAMILY p. 72 



Flowers not in spikes, or flowers imperfect 27 



27. Pistils more than 1, separate 



CROWFOOT FAMILY in part p. 95 



Pistil 1 ; if more than 1, not separate 28 



28. Ovary inferior 29 



Ovary superior 30 



29. Flowers small, clustered in 5-lobed involucres 



FOUR-O'CLOCK FAMILY p. 81 



Flowers without involucres 31 



30. Calyx small, whitish SANDALWOOD FAMILY p. 75 



Calvx large, conspicuously colored 



' BIRTHWORT FAMILY p. 76 



31. Style 1 NETTLE FAMILY p. 74 



Stvles 3; sap milky SPURGE FAMILY in part p. 181 



Stvles 5 ORPINE FAMILY in part p. 138 



Styles 10 POKEWEED FAMILY p. 80 



32. Corolla borne on the receptacle 22 



Corolla borne on the calyx 50 



2)2- Leaves fleshy 34 



Not thus 35 



31 



